From 18fec5128b6fd9712f63e306f03f16833f2599b2 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Tue, 12 Feb 2013 08:20:14 +0400 Subject: EXPLAIN DELETE for MariaDB - Backported the code to 10.0-base - Removed incorrect assert --- sql/my_apc.h | 2 + sql/sql_delete.cc | 221 ++++++++++++++++++++++++++++++++++++++++++++++++++---- sql/sql_lex.cc | 31 +++++--- sql/sql_lex.h | 48 ++++++++++++ sql/sql_parse.cc | 82 ++++++++++++++------ sql/sql_select.cc | 158 ++++++++++++++++++++++++++++++++------ sql/sql_select.h | 22 ++++++ sql/sql_show.cc | 4 +- sql/sql_string.h | 32 ++++++++ sql/sql_update.cc | 5 +- sql/sql_yacc.yy | 10 ++- 11 files changed, 537 insertions(+), 78 deletions(-) (limited to 'sql') diff --git a/sql/my_apc.h b/sql/my_apc.h index 7f19809c082..ee94595e78f 100644 --- a/sql/my_apc.h +++ b/sql/my_apc.h @@ -64,6 +64,8 @@ public: { return test(apc_calls); } + + inline bool is_enabled() { return enabled; } /* Functor class for calls you can schedule */ class Apc_call diff --git a/sql/sql_delete.cc b/sql/sql_delete.cc index 4bcb62ef764..d7a612f3d56 100644 --- a/sql/sql_delete.cc +++ b/sql/sql_delete.cc @@ -40,6 +40,129 @@ #include "records.h" // init_read_record, #include "sql_derived.h" // mysql_handle_list_of_derived // end_read_record + + +/* + @brief + Print query plan of a single-table DELETE command + + @detail + This function is used by EXPLAIN DELETE and by SHOW EXPLAIN when it is + invoked on a running DELETE statement. +*/ + +int Delete_plan::print_explain(select_result_sink *output, uint8 explain_flags, + bool *printed_anything) +{ + if (deleting_all_rows || impossible_where) + { + const char *msg= deleting_all_rows? "Deleting all rows": "Impossible where"; + if (print_explain_message_line(output, explain_flags, 1/*select number*/, + "SIMPLE", msg)) + { + return 1; + } + *printed_anything= true; + return 0; + } + + select_lex->set_explain_type(FALSE); + /* + Print an EXPLAIN line. We dont have join, so we can't directly use + JOIN::print_explain. + We do have a SELECT_LEX (TODO but how is it useful? it has select_type.. + and that's it?) + */ + + enum join_type jtype; + if (select && select->quick) + { + int quick_type= select->quick->get_type(); + if ((quick_type == QUICK_SELECT_I::QS_TYPE_INDEX_MERGE) || + (quick_type == QUICK_SELECT_I::QS_TYPE_INDEX_INTERSECT) || + (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_INTERSECT) || + (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_UNION)) + jtype= JT_INDEX_MERGE; + else + jtype= JT_RANGE; + } + else + { + if (index == MAX_KEY) + jtype= JT_ALL; + else + jtype= JT_NEXT; + } + + StringBuffer<128> possible_keys_line; + make_possible_keys_line(table, possible_keys, &possible_keys_line); + + const char *key_name; + const char *key_len; + + StringBuffer<128> key_str; + StringBuffer<128> key_len_str; + StringBuffer<128> extra_str; + + /* Calculate key_len */ + if (select && select->quick) + { + select->quick->add_keys_and_lengths(&key_str, &key_len_str); + key_name= key_str.c_ptr(); + key_len= key_len_str.c_ptr(); + } + else + { + key_name= (index == MAX_KEY)? NULL : table->key_info[index].name; + key_len= NULL; + } + + if (select && select->cond) + extra_str.append(STRING_WITH_LEN("Using where")); + if (select && select->quick && + select->quick->get_type() == QUICK_SELECT_I::QS_TYPE_RANGE) + { + explain_append_mrr_info((QUICK_RANGE_SELECT*)select->quick, &extra_str); + } + + if (using_filesort) + { + if (extra_str.length() !=0) + extra_str.append(STRING_WITH_LEN("; ")); + extra_str.append(STRING_WITH_LEN("Using filesort")); + } + + /* + Single-table DELETE commands do not do "Using temporary". + "Using index condition" is also not possible (which is an unjustified limitation) + */ + + print_explain_row(output, explain_flags, + 1, /* id */ + select_lex->type, + table->pos_in_table_list->alias, + // partitions, + jtype, + possible_keys_line.length()? possible_keys_line.c_ptr(): NULL, + key_name, + key_len, + NULL, /* 'ref' is always NULL in single-table EXPLAIN DELETE */ + select ? select->records : table_rows, + extra_str.c_ptr()); + + *printed_anything= true; + + for (SELECT_LEX_UNIT *unit= select_lex->first_inner_unit(); + unit; + unit= unit->next_unit()) + { + if (unit->print_explain(output, explain_flags, printed_anything)) + return 1; + } + return 0; +} + + /** Implement DELETE SQL word. @@ -61,12 +184,16 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, bool const_cond_result; ha_rows deleted= 0; bool reverse= FALSE; + bool err= true; ORDER *order= (ORDER *) ((order_list && order_list->elements) ? order_list->first : NULL); - uint usable_index= MAX_KEY; SELECT_LEX *select_lex= &thd->lex->select_lex; killed_state killed_status= NOT_KILLED; THD::enum_binlog_query_type query_type= THD::ROW_QUERY_TYPE; + + Delete_plan query_plan; + query_plan.index= MAX_KEY; + query_plan.using_filesort= FALSE; DBUG_ENTER("mysql_delete"); if (open_and_lock_tables(thd, table_list, TRUE, 0)) @@ -90,6 +217,8 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, } thd_proc_info(thd, "init"); table->map=1; + query_plan.select_lex= &thd->lex->select_lex; + query_plan.table= table; if (mysql_prepare_delete(thd, table_list, &conds)) DBUG_RETURN(TRUE); @@ -163,6 +292,11 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, table->file->info(HA_STATUS_VARIABLE | HA_STATUS_NO_LOCK); ha_rows const maybe_deleted= table->file->stats.records; DBUG_PRINT("debug", ("Trying to use delete_all_rows()")); + + query_plan.set_delete_all_rows(maybe_deleted); + if (thd->lex->describe) + goto exit_without_my_ok; + if (!(error=table->file->ha_delete_all_rows())) { /* @@ -187,7 +321,12 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, Item::cond_result result; conds= remove_eq_conds(thd, conds, &result); if (result == Item::COND_FALSE) // Impossible where + { limit= 0; + query_plan.set_impossible_where(); + if (thd->lex->describe) + goto exit_without_my_ok; + } } #ifdef WITH_PARTITION_STORAGE_ENGINE @@ -195,6 +334,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, { free_underlaid_joins(thd, select_lex); // No matching record + //psergey-explain-todo: No-partitions used EXPLAIN here.. my_ok(thd, 0); DBUG_RETURN(0); } @@ -211,6 +351,10 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, DBUG_RETURN(TRUE); if ((select && select->check_quick(thd, safe_update, limit)) || !limit) { + query_plan.set_impossible_where(); + if (thd->lex->describe) + goto exit_without_my_ok; + delete select; free_underlaid_joins(thd, select_lex); /* @@ -243,26 +387,46 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, if (order) { - uint length= 0; - SORT_FIELD *sortorder; - ha_rows examined_rows; - ha_rows found_rows; - table->update_const_key_parts(conds); order= simple_remove_const(order, conds); - bool need_sort; if (select && select->quick && select->quick->unique_key_range()) { // Single row select (always "ordered") - need_sort= FALSE; - usable_index= MAX_KEY; + query_plan.using_filesort= FALSE; + query_plan.index= MAX_KEY; } else - usable_index= get_index_for_order(order, table, select, limit, - &need_sort, &reverse); - if (need_sort) + query_plan.index= get_index_for_order(order, table, select, limit, + &query_plan.using_filesort, + &reverse); + } + + query_plan.select= select; + query_plan.possible_keys= table->quick_keys; + query_plan.table_rows= table->file->stats.records; + thd->lex->delete_plan= &query_plan; + + /* + Ok, we have generated a query plan for the DELETE. + - if we're running EXPLAIN DELETE, goto produce explain output + - otherwise, execute the query plan + */ + if (thd->lex->describe) + goto exit_without_my_ok; + + thd->apc_target.enable(); + DBUG_EXECUTE_IF("show_explain_probe_delete_exec_start", + dbug_serve_apcs(thd, 1);); + + if (query_plan.using_filesort) + { + ha_rows examined_rows; + ha_rows found_rows; + uint length= 0; + SORT_FIELD *sortorder; + { - DBUG_ASSERT(usable_index == MAX_KEY); + DBUG_ASSERT(query_plan.index == MAX_KEY); table->sort.io_cache= (IO_CACHE *) my_malloc(sizeof(IO_CACHE), MYF(MY_FAE | MY_ZEROFILL | MY_THREAD_SPECIFIC)); @@ -276,6 +440,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, { delete select; free_underlaid_joins(thd, &thd->lex->select_lex); + thd->apc_target.disable(); DBUG_RETURN(TRUE); } thd->examined_row_count+= examined_rows; @@ -294,19 +459,21 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, { delete select; free_underlaid_joins(thd, select_lex); + thd->apc_target.disable(); DBUG_RETURN(TRUE); } - if (usable_index == MAX_KEY || (select && select->quick)) + if (query_plan.index == MAX_KEY || (select && select->quick)) { if (init_read_record(&info, thd, table, select, 1, 1, FALSE)) { delete select; free_underlaid_joins(thd, select_lex); + thd->apc_target.disable(); DBUG_RETURN(TRUE); } } else - init_read_record_idx(&info, thd, table, 1, usable_index, reverse); + init_read_record_idx(&info, thd, table, 1, query_plan.index, reverse); init_ftfuncs(thd, select_lex, 1); thd_proc_info(thd, "updating"); @@ -398,6 +565,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, if (options & OPTION_QUICK) (void) table->file->extra(HA_EXTRA_NORMAL); + thd->apc_target.disable(); cleanup: /* Invalidate the table in the query cache if something changed. This must @@ -458,6 +626,29 @@ cleanup: DBUG_PRINT("info",("%ld records deleted",(long) deleted)); } DBUG_RETURN(error >= 0 || thd->is_error()); + + /* Special exits */ +exit_without_my_ok: + thd->lex->delete_plan= &query_plan; + + select_send *result; + bool printed_anything; + if (!(result= new select_send())) + return 1; /* purecov: inspected */ + List dummy; /* note: looked in 5.6 and they too use a dummy list like this */ + result->prepare(dummy, &thd->lex->unit); + thd->send_explain_fields(result); + int err2= thd->lex->print_explain(result, 0 /* explain flags*/, &printed_anything); + + if (err2) + result->abort_result_set(); + else + result->send_eof(); + + delete select; + free_underlaid_joins(thd, select_lex); + //table->set_keyread(false); + DBUG_RETURN((err || thd->is_error() || thd->killed) ? 1 : 0); } diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc index b8ce3b6720e..74e4b3e1162 100644 --- a/sql/sql_lex.cc +++ b/sql/sql_lex.cc @@ -448,6 +448,7 @@ void lex_start(THD *thd) lex->thd= lex->unit.thd= thd; + lex->delete_plan= NULL; lex->context_stack.empty(); lex->unit.init_query(); lex->unit.init_select(); @@ -2557,6 +2558,7 @@ LEX::LEX() INITIAL_LEX_PLUGIN_LIST_SIZE, 0); reset_query_tables_list(TRUE); mi.init(); + delete_plan= NULL; } @@ -4166,12 +4168,17 @@ bool st_select_lex::is_merged_child_of(st_select_lex *ancestor) return all_merged; } - -int print_explain_message_line(select_result_sink *result, - SELECT_LEX *select_lex, - bool on_the_fly, - uint8 options, - const char *message); +int LEX::print_explain(select_result_sink *output, uint8 explain_flags, + bool *printed_anything) +{ + if (delete_plan) + { + delete_plan->print_explain(output, explain_flags, printed_anything); + return 0; + } + int res= unit.print_explain(output, explain_flags, printed_anything); + return res; +} int st_select_lex::print_explain(select_result_sink *output, @@ -4235,8 +4242,9 @@ int st_select_lex::print_explain(select_result_sink *output, DBUG_ASSERT(join->have_query_plan == JOIN::QEP_DELETED); msg= "Query plan already deleted"; } - res= print_explain_message_line(output, this, TRUE /* on_the_fly */, - 0, msg); + set_explain_type(TRUE/* on_the_fly */); + res= print_explain_message_line(output, 0/*options*/, select_number, type, + msg); } err: return res; @@ -4256,9 +4264,10 @@ int st_select_lex_unit::print_explain(select_result_sink *output, EXPLAIN state" error. */ const char *msg="Query plan already deleted"; - res= print_explain_message_line(output, first, TRUE /* on_the_fly */, - 0, msg); - return 0; + first->set_explain_type(TRUE/* on_the_fly */); + res= print_explain_message_line(output, 0/*options*/, first->select_number, + first->type, msg); + return res; } for (SELECT_LEX *sl= first; sl; sl= sl->next_select()) diff --git a/sql/sql_lex.h b/sql/sql_lex.h index be7cdd8ca1d..af35ccb01b0 100644 --- a/sql/sql_lex.h +++ b/sql/sql_lex.h @@ -2344,6 +2344,48 @@ protected: LEX *m_lex; }; +class Delete_plan; +class SQL_SELECT; + +/* Query plan of a single-table DELETE */ +class Delete_plan +{ + bool deleting_all_rows; + bool impossible_where; +public: + + TABLE *table; + SQL_SELECT *select; + uint index; + ha_rows table_rows; /* Use if select==NULL */ + bool using_filesort; + key_map possible_keys; + + /* + Top-level select_lex. Most of its fields are not used, we need it only to + get to the subqueries. + */ + SELECT_LEX *select_lex; + + /* Construction functions */ + Delete_plan() : + deleting_all_rows(false), impossible_where(false), using_filesort(false) {} + + /* Set this query plan to be a plan to make a call to h->delete_all_rows() */ + void set_delete_all_rows(ha_rows rows_arg) + { + deleting_all_rows= true; + table_rows= rows_arg; + } + + /* Set this plan to be a plan to do nothing because of impossible WHRE*/ + void set_impossible_where() { impossible_where= true; } + + int print_explain(select_result_sink *output, uint8 explain_flags, + bool *printed_anything); +}; + + /* The state of the lex parsing. This is saved in the THD struct */ struct LEX: public Query_tables_list @@ -2355,6 +2397,9 @@ struct LEX: public Query_tables_list /* list of all SELECT_LEX */ SELECT_LEX *all_selects_list; + /* For single-table DELETE: its query plan */ + Delete_plan *delete_plan; + char *length,*dec,*change; LEX_STRING name; char *help_arg; @@ -2769,6 +2814,9 @@ struct LEX: public Query_tables_list } return FALSE; } + + int print_explain(select_result_sink *output, uint8 explain_flags, + bool *printed_anything); }; diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc index 0abb249d97b..d5fd5c1b32d 100644 --- a/sql/sql_parse.cc +++ b/sql/sql_parse.cc @@ -3212,7 +3212,8 @@ end_with_restore_list: { DBUG_ASSERT(first_table == all_tables && first_table != 0); TABLE_LIST *aux_tables= thd->lex->auxiliary_table_list.first; - multi_delete *del_result; + bool explain= test(lex->describe); + select_result *result; if ((res= multi_delete_precheck(thd, all_tables))) break; @@ -3227,37 +3228,72 @@ end_with_restore_list: if ((res= open_and_lock_tables(thd, all_tables, TRUE, 0))) break; - MYSQL_MULTI_DELETE_START(thd->query()); + if (!explain) + { + MYSQL_MULTI_DELETE_START(thd->query()); + } + if ((res= mysql_multi_delete_prepare(thd))) { - MYSQL_MULTI_DELETE_DONE(1, 0); + if (!explain) + { + MYSQL_MULTI_DELETE_DONE(1, 0); + } goto error; } - if (!thd->is_fatal_error && - (del_result= new multi_delete(aux_tables, lex->table_count))) - { - res= mysql_select(thd, &select_lex->ref_pointer_array, - select_lex->get_table_list(), - select_lex->with_wild, - select_lex->item_list, - select_lex->where, - 0, (ORDER *)NULL, (ORDER *)NULL, (Item *)NULL, - (ORDER *)NULL, - (select_lex->options | thd->variables.option_bits | - SELECT_NO_JOIN_CACHE | SELECT_NO_UNLOCK | - OPTION_SETUP_TABLES_DONE) & ~OPTION_BUFFER_RESULT, - del_result, unit, select_lex); - res|= thd->is_error(); - MYSQL_MULTI_DELETE_DONE(res, del_result->num_deleted()); - if (res) - del_result->abort_result_set(); - delete del_result; + if (!thd->is_fatal_error) + { + if (explain) + { + result= new select_send(); + if (thd->send_explain_fields(result)) + { + delete result; + result= NULL; + } + select_lex->set_explain_type(FALSE); + } + else + result= new multi_delete(aux_tables, lex->table_count); + + if (result) + { + res= mysql_select(thd, &select_lex->ref_pointer_array, + select_lex->get_table_list(), + select_lex->with_wild, + select_lex->item_list, + select_lex->where, + 0, (ORDER *)NULL, (ORDER *)NULL, (Item *)NULL, + (ORDER *)NULL, + (select_lex->options | thd->variables.option_bits | + SELECT_NO_JOIN_CACHE | SELECT_NO_UNLOCK | + OPTION_SETUP_TABLES_DONE) & ~OPTION_BUFFER_RESULT, + result, unit, select_lex); + res|= thd->is_error(); + + if (!explain) + { + MYSQL_MULTI_DELETE_DONE(res, del_result->num_deleted()); + } + + if (res) + result->abort_result_set(); /* for both DELETE and EXPLAIN DELETE */ + else + { + if (explain) + result->send_eof(); + } + delete result; + } } else { res= TRUE; // Error - MYSQL_MULTI_DELETE_DONE(1, 0); + if (!explain) + { + MYSQL_MULTI_DELETE_DONE(1, 0); + } } break; } diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 41c0b07bc49..230355c550e 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -21594,23 +21594,20 @@ void JOIN::clear() /* Print an EXPLAIN line with all NULLs and given message in the 'Extra' column */ + int print_explain_message_line(select_result_sink *result, - SELECT_LEX *select_lex, - bool on_the_fly, uint8 options, + uint select_number, + const char *select_type, const char *message) { const CHARSET_INFO *cs= system_charset_info; Item *item_null= new Item_null(); List item_list; - if (on_the_fly) - select_lex->set_explain_type(on_the_fly); - - item_list.push_back(new Item_int((int32) - select_lex->select_number)); - item_list.push_back(new Item_string(select_lex->type, - strlen(select_lex->type), cs)); + item_list.push_back(new Item_int((int32) select_number)); + item_list.push_back(new Item_string(select_type, + strlen(select_type), cs)); for (uint i=0 ; i < 7; i++) item_list.push_back(item_null); if (options & DESCRIBE_PARTITIONS) @@ -21626,6 +21623,104 @@ int print_explain_message_line(select_result_sink *result, } +/* + Make a comma-separated list of possible_keys names and add it into the string +*/ + +void make_possible_keys_line(TABLE *table, key_map possible_keys, String *line) +{ + if (!possible_keys.is_clear_all()) + { + uint j; + for (j=0 ; j < table->s->keys ; j++) + { + if (possible_keys.is_set(j)) + { + if (line->length()) + line->append(','); + line->append(table->key_info[j].name, + strlen(table->key_info[j].name), + system_charset_info); + } + } + } +} + +/* + Print an EXPLAIN output row, based on information provided in the parameters + + @note + Parameters that may have NULL value in EXPLAIN output, should be passed + (char*)NULL. + + @return + 0 - OK + 1 - OOM Error +*/ + +int print_explain_row(select_result_sink *result, + uint8 options, + uint select_number, + const char *select_type, + const char *table_name, + //const char *partitions, (todo) + enum join_type jtype, + const char *possible_keys, + const char *index, + const char *key_len, + const char *ref, + ha_rows rows, + const char *extra) +{ + const CHARSET_INFO *cs= system_charset_info; + Item *item_null= new Item_null(); + List item_list; + Item *item; + + item_list.push_back(new Item_int((int32) select_number)); + item_list.push_back(new Item_string(select_type, + strlen(select_type), cs)); + item_list.push_back(new Item_string(table_name, + strlen(table_name), cs)); + if (options & DESCRIBE_PARTITIONS) + item_list.push_back(item_null); // psergey-todo: produce proper value + + const char *jtype_str= join_type_str[jtype]; + item_list.push_back(new Item_string(jtype_str, + strlen(jtype_str), cs)); + + item= possible_keys? new Item_string(possible_keys, strlen(possible_keys), + cs) : item_null; + item_list.push_back(item); + + /* 'index */ + item= index ? new Item_string(index, strlen(index), cs) : item_null; + item_list.push_back(item); + + /* 'key_len */ + item= key_len ? new Item_string(key_len, strlen(key_len), cs) : item_null; + item_list.push_back(item); + + /* 'ref' */ + item= ref ? new Item_string(ref, strlen(ref), cs) : item_null; + item_list.push_back(item); + + /* 'rows' */ + item_list.push_back(new Item_int(rows, + MY_INT64_NUM_DECIMAL_DIGITS)); + /* 'filtered' */ + if (options & DESCRIBE_EXTENDED) + item_list.push_back(item_null); + + /* 'Extra' */ + item_list.push_back(new Item_string(extra, strlen(extra), cs)); + + if (result->send_data(item_list)) + return 1; + return 0; +} + + int print_fake_select_lex_join(select_result_sink *result, bool on_the_fly, SELECT_LEX *select_lex, uint8 explain_flags) { @@ -21705,6 +21800,26 @@ int print_fake_select_lex_join(select_result_sink *result, bool on_the_fly, } +/* + Append MRR information from quick select to the given string +*/ + +void explain_append_mrr_info(QUICK_RANGE_SELECT *quick, String *res) +{ + char mrr_str_buf[128]; + mrr_str_buf[0]=0; + int len; + handler *h= quick->head->file; + len= h->multi_range_read_explain_info(quick->mrr_flags, mrr_str_buf, + sizeof(mrr_str_buf)); + if (len > 0) + { + res->append(STRING_WITH_LEN("; ")); + res->append(mrr_str_buf, len); + } +} + + /** EXPLAIN handling. @@ -21746,8 +21861,12 @@ int JOIN::print_explain(select_result_sink *result, uint8 explain_flags, */ if (message) { - if (print_explain_message_line(result, join->select_lex, on_the_fly, - explain_flags, message)) + if (on_the_fly) + join->select_lex->set_explain_type(on_the_fly); + + if (print_explain_message_line(result, explain_flags, + join->select_lex->select_number, + join->select_lex->type, message)) error= 1; } @@ -21762,7 +21881,7 @@ int JOIN::print_explain(select_result_sink *result, uint8 explain_flags, join->select_lex->master_unit()->derived->is_materialized_derived()) { table_map used_tables=0; - //if (!join->select_lex->type) + if (on_the_fly) join->select_lex->set_explain_type(on_the_fly); @@ -22171,19 +22290,8 @@ int JOIN::print_explain(select_result_sink *result, uint8 explain_flags, */ if (quick_type == QUICK_SELECT_I::QS_TYPE_RANGE) { - char mrr_str_buf[128]; - mrr_str_buf[0]=0; - int len; - uint mrr_flags= - ((QUICK_RANGE_SELECT*)(tab->select->quick))->mrr_flags; - len= table->file->multi_range_read_explain_info(mrr_flags, - mrr_str_buf, - sizeof(mrr_str_buf)); - if (len > 0) - { - extra.append(STRING_WITH_LEN("; ")); - extra.append(mrr_str_buf, len); - } + explain_append_mrr_info((QUICK_RANGE_SELECT*)(tab->select->quick), + &extra); } if (need_tmp_table) diff --git a/sql/sql_select.h b/sql/sql_select.h index 638de926d75..61a72357d84 100644 --- a/sql/sql_select.h +++ b/sql/sql_select.h @@ -1804,6 +1804,28 @@ void eliminate_tables(JOIN *join); /* Index Condition Pushdown entry point function */ void push_index_cond(JOIN_TAB *tab, uint keyno); +/* EXPLAIN-related utility functions */ +int print_explain_message_line(select_result_sink *result, + uint8 options, + uint select_number, + const char *select_type, + const char *message); +void explain_append_mrr_info(QUICK_RANGE_SELECT *quick, String *res); +int print_explain_row(select_result_sink *result, + uint8 options, + uint select_number, + const char *select_type, + const char *table_name, + //const char *partitions, (todo) + enum join_type jtype, + const char *possible_keys, + const char *index, + const char *key_len, + const char *ref, + ha_rows rows, + const char *extra); +void make_possible_keys_line(TABLE *table, key_map possible_keys, String *line); + /**************************************************************************** Temporary table support for SQL Runtime ***************************************************************************/ diff --git a/sql/sql_show.cc b/sql/sql_show.cc index 095ad409a94..f3bb14b6e9f 100644 --- a/sql/sql_show.cc +++ b/sql/sql_show.cc @@ -2337,8 +2337,8 @@ void Show_explain_request::call_in_target_thread() DBUG_ASSERT(current_thd == target_thd); set_current_thd(request_thd); - if (target_thd->lex->unit.print_explain(explain_buf, 0 /* explain flags*/, - &printed_anything)) + if (target_thd->lex->print_explain(explain_buf, 0 /* explain flags*/, + &printed_anything)) { failed_to_produce= TRUE; } diff --git a/sql/sql_string.h b/sql/sql_string.h index 58cda343dac..e08b7a2581f 100644 --- a/sql/sql_string.h +++ b/sql/sql_string.h @@ -500,6 +500,38 @@ public: } }; + +// The following class is a backport from MySQL 5.6: +/** + String class wrapper with a preallocated buffer of size buff_sz + + This class allows to replace sequences of: + char buff[12345]; + String str(buff, sizeof(buff)); + str.length(0); + with a simple equivalent declaration: + StringBuffer<12345> str; +*/ + +template +class StringBuffer : public String +{ + char buff[buff_sz]; + +public: + StringBuffer() : String(buff, buff_sz, &my_charset_bin) { length(0); } + explicit StringBuffer(const CHARSET_INFO *cs) : String(buff, buff_sz, cs) + { + length(0); + } + StringBuffer(const char *str, size_t length, const CHARSET_INFO *cs) + : String(buff, buff_sz, cs) + { + set(str, length, cs); + } +}; + + static inline bool check_if_only_end_space(CHARSET_INFO *cs, const char *str, const char *end) diff --git a/sql/sql_update.cc b/sql/sql_update.cc index 28b9fe7eacd..84adfc2c3f5 100644 --- a/sql/sql_update.cc +++ b/sql/sql_update.cc @@ -1394,7 +1394,10 @@ bool mysql_multi_update(THD *thd, thd->abort_on_warning= test(thd->variables.sql_mode & (MODE_STRICT_TRANS_TABLES | MODE_STRICT_ALL_TABLES)); - +/* + psergey-explain-todo: + This is the place where EXPLAIN should be handled. +*/ List total_list; res= mysql_select(thd, &select_lex->ref_pointer_array, diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy index 9664aad1e19..7bac9c8ded7 100644 --- a/sql/sql_yacc.yy +++ b/sql/sql_yacc.yy @@ -11881,13 +11881,21 @@ describe: opt_describe_column {} | describe_command opt_extended_describe { Lex->describe|= DESCRIBE_NORMAL; } - select + explanable_command { LEX *lex=Lex; lex->select_lex.options|= SELECT_DESCRIBE; } ; +explanable_command: + select + | insert + | replace + | update + | delete + ; + describe_command: DESC | DESCRIBE -- cgit v1.2.1 From d2995031d9214206689660069024525808c8a683 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Tue, 12 Feb 2013 14:37:08 +0400 Subject: SHOW EXPLAIN for MariaDB - Support [SHOW] EXPLAIN UPDATE (needs code cleanup). --- sql/sql_delete.cc | 26 +++++++++-- sql/sql_lex.cc | 8 ++-- sql/sql_lex.h | 41 +++++++++++------ sql/sql_select.cc | 3 +- sql/sql_update.cc | 134 +++++++++++++++++++++++++++++++++++++++++++----------- 5 files changed, 164 insertions(+), 48 deletions(-) (limited to 'sql') diff --git a/sql/sql_delete.cc b/sql/sql_delete.cc index d7a612f3d56..df659871a64 100644 --- a/sql/sql_delete.cc +++ b/sql/sql_delete.cc @@ -54,9 +54,27 @@ int Delete_plan::print_explain(select_result_sink *output, uint8 explain_flags, bool *printed_anything) { - if (deleting_all_rows || impossible_where) + if (deleting_all_rows) { - const char *msg= deleting_all_rows? "Deleting all rows": "Impossible where"; + const char *msg= "Deleting all rows"; + if (print_explain_message_line(output, explain_flags, 1/*select number*/, + "SIMPLE", msg)) + { + return 1; + } + *printed_anything= true; + return 0; + } + return Update_plan::print_explain(output, explain_flags, printed_anything); +} + + +int Update_plan::print_explain(select_result_sink *output, uint8 explain_flags, + bool *printed_anything) +{ + if (impossible_where) + { + const char *msg= "Impossible where"; if (print_explain_message_line(output, explain_flags, 1/*select number*/, "SIMPLE", msg)) { @@ -404,7 +422,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, query_plan.select= select; query_plan.possible_keys= table->quick_keys; query_plan.table_rows= table->file->stats.records; - thd->lex->delete_plan= &query_plan; + thd->lex->upd_del_plan= &query_plan; /* Ok, we have generated a query plan for the DELETE. @@ -629,7 +647,7 @@ cleanup: /* Special exits */ exit_without_my_ok: - thd->lex->delete_plan= &query_plan; + thd->lex->upd_del_plan= &query_plan; select_send *result; bool printed_anything; diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc index 74e4b3e1162..714ab373b17 100644 --- a/sql/sql_lex.cc +++ b/sql/sql_lex.cc @@ -448,7 +448,7 @@ void lex_start(THD *thd) lex->thd= lex->unit.thd= thd; - lex->delete_plan= NULL; + lex->upd_del_plan= NULL; lex->context_stack.empty(); lex->unit.init_query(); lex->unit.init_select(); @@ -2558,7 +2558,7 @@ LEX::LEX() INITIAL_LEX_PLUGIN_LIST_SIZE, 0); reset_query_tables_list(TRUE); mi.init(); - delete_plan= NULL; + upd_del_plan= NULL; } @@ -4171,9 +4171,9 @@ bool st_select_lex::is_merged_child_of(st_select_lex *ancestor) int LEX::print_explain(select_result_sink *output, uint8 explain_flags, bool *printed_anything) { - if (delete_plan) + if (upd_del_plan) { - delete_plan->print_explain(output, explain_flags, printed_anything); + upd_del_plan->print_explain(output, explain_flags, printed_anything); return 0; } int res= unit.print_explain(output, explain_flags, printed_anything); diff --git a/sql/sql_lex.h b/sql/sql_lex.h index af35ccb01b0..588ad172a3c 100644 --- a/sql/sql_lex.h +++ b/sql/sql_lex.h @@ -2347,29 +2347,48 @@ protected: class Delete_plan; class SQL_SELECT; -/* Query plan of a single-table DELETE */ -class Delete_plan +/* + Query plan of a single-table UPDATE. + (This is actually a plan for single-table DELETE also) +*/ +class Update_plan { - bool deleting_all_rows; +protected: bool impossible_where; public: - TABLE *table; SQL_SELECT *select; uint index; ha_rows table_rows; /* Use if select==NULL */ - bool using_filesort; - key_map possible_keys; - /* Top-level select_lex. Most of its fields are not used, we need it only to get to the subqueries. */ SELECT_LEX *select_lex; + + key_map possible_keys; + bool using_filesort; + + /* Set this plan to be a plan to do nothing because of impossible WHRE*/ + void set_impossible_where() { impossible_where= true; } + + virtual int print_explain(select_result_sink *output, uint8 explain_flags, + bool *printed_anything); + virtual ~Update_plan() {} + + Update_plan() : impossible_where(false), using_filesort(false) {} +}; + + +/* Query plan of a single-table DELETE */ +class Delete_plan : public Update_plan +{ + bool deleting_all_rows; +public: /* Construction functions */ Delete_plan() : - deleting_all_rows(false), impossible_where(false), using_filesort(false) {} + deleting_all_rows(false) {} /* Set this query plan to be a plan to make a call to h->delete_all_rows() */ void set_delete_all_rows(ha_rows rows_arg) @@ -2377,10 +2396,6 @@ public: deleting_all_rows= true; table_rows= rows_arg; } - - /* Set this plan to be a plan to do nothing because of impossible WHRE*/ - void set_impossible_where() { impossible_where= true; } - int print_explain(select_result_sink *output, uint8 explain_flags, bool *printed_anything); }; @@ -2398,7 +2413,7 @@ struct LEX: public Query_tables_list SELECT_LEX *all_selects_list; /* For single-table DELETE: its query plan */ - Delete_plan *delete_plan; + Update_plan *upd_del_plan; char *length,*dec,*change; LEX_STRING name; diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 230355c550e..d9177b9240e 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -10756,7 +10756,8 @@ void JOIN::cleanup(bool full) DBUG_ENTER("JOIN::cleanup"); DBUG_PRINT("enter", ("full %u", (uint) full)); - have_query_plan= QEP_DELETED; + if (full) + have_query_plan= QEP_DELETED; //psergey: this is a problem! if (table) { diff --git a/sql/sql_update.cc b/sql/sql_update.cc index 84adfc2c3f5..11cb493da97 100644 --- a/sql/sql_update.cc +++ b/sql/sql_update.cc @@ -260,7 +260,7 @@ int mysql_update(THD *thd, bool can_compare_record; int res; int error, loc_error; - uint used_index, dup_key_found; + uint dup_key_found; bool need_sort= TRUE; bool reverse= FALSE; #ifndef NO_EMBEDDED_ACCESS_CHECKS @@ -270,12 +270,15 @@ int mysql_update(THD *thd, ha_rows updated, found; key_map old_covering_keys; TABLE *table; - SQL_SELECT *select; + SQL_SELECT *select= NULL; READ_RECORD info; SELECT_LEX *select_lex= &thd->lex->select_lex; ulonglong id; List all_fields; killed_state killed_status= NOT_KILLED; + Update_plan query_plan; + query_plan.index= MAX_KEY; + query_plan.using_filesort= FALSE; DBUG_ENTER("mysql_update"); if (open_tables(thd, &table_list, &table_count, 0)) @@ -314,6 +317,8 @@ int mysql_update(THD *thd, table->covering_keys= table->s->keys_in_use; table->quick_keys.clear_all(); + query_plan.select_lex= &thd->lex->select_lex; + query_plan.table= table; #ifndef NO_EMBEDDED_ACCESS_CHECKS /* Force privilege re-checking for views after they have been opened. */ want_privilege= (table_list->view ? UPDATE_ACL : @@ -370,7 +375,12 @@ int mysql_update(THD *thd, Item::cond_result cond_value; conds= remove_eq_conds(thd, conds, &cond_value); if (cond_value == Item::COND_FALSE) + { limit= 0; // Impossible WHERE + query_plan.set_impossible_where(); + if (thd->lex->describe) + goto exit_without_my_ok; + } } /* @@ -400,6 +410,10 @@ int mysql_update(THD *thd, if (error || !limit || thd->is_error() || (select && select->check_quick(thd, safe_update, limit))) { + query_plan.set_impossible_where(); + if (thd->lex->describe) + goto exit_without_my_ok; + delete select; free_underlaid_joins(thd, select_lex); /* @@ -438,16 +452,16 @@ int mysql_update(THD *thd, if (select && select->quick && select->quick->unique_key_range()) { // Single row select (always "ordered"): Ok to use with key field UPDATE need_sort= FALSE; - used_index= MAX_KEY; + query_plan.index= MAX_KEY; used_key_is_modified= FALSE; } else { - used_index= get_index_for_order(order, table, select, limit, - &need_sort, &reverse); + query_plan.index= get_index_for_order(order, table, select, limit, + &need_sort, &reverse); if (select && select->quick) { - DBUG_ASSERT(need_sort || used_index == select->quick->index); + DBUG_ASSERT(need_sort || query_plan.index == select->quick->index); used_key_is_modified= (!select->quick->unique_key_range() && select->quick->is_keys_used(table->write_set)); } @@ -455,14 +469,37 @@ int mysql_update(THD *thd, { if (need_sort) { // Assign table scan index to check below for modified key fields: - used_index= table->file->key_used_on_scan; + query_plan.index= table->file->key_used_on_scan; } - if (used_index != MAX_KEY) + if (query_plan.index != MAX_KEY) { // Check if we are modifying a key that we are used to search with: - used_key_is_modified= is_key_used(table, used_index, table->write_set); + used_key_is_modified= is_key_used(table, query_plan.index, table->write_set); } } } + + /* + Query optimization is finished at this point. + - Save the decisions in the query plan + - if we're running EXPLAIN UPDATE, get out + */ + query_plan.select= select; + query_plan.possible_keys= table->quick_keys; + query_plan.table_rows= table->file->stats.records; + thd->lex->upd_del_plan= &query_plan; + + /* + Ok, we have generated a query plan for the UPDATE. + - if we're running EXPLAIN UPDATE, goto produce explain output + - otherwise, execute the query plan + */ + if (thd->lex->describe) + goto exit_without_my_ok; + + thd->apc_target.enable(); + DBUG_EXECUTE_IF("show_explain_probe_update_exec_start", + dbug_serve_apcs(thd, 1);); + if (used_key_is_modified || order || partition_key_modified(table, table->write_set)) @@ -476,8 +513,8 @@ int mysql_update(THD *thd, DBUG_ASSERT(table->read_set == &table->def_read_set); DBUG_ASSERT(table->write_set == &table->def_write_set); - if (used_index < MAX_KEY && old_covering_keys.is_set(used_index)) - table->add_read_columns_used_by_index(used_index); + if (query_plan.index < MAX_KEY && old_covering_keys.is_set(query_plan.index)) + table->add_read_columns_used_by_index(query_plan.index); else table->use_all_columns(); @@ -534,22 +571,22 @@ int mysql_update(THD *thd, /* When we get here, we have one of the following options: - A. used_index == MAX_KEY + A. query_plan.index == MAX_KEY This means we should use full table scan, and start it with init_read_record call - B. used_index != MAX_KEY + B. query_plan.index != MAX_KEY B.1 quick select is used, start the scan with init_read_record B.2 quick select is not used, this is full index scan (with LIMIT) Full index scan must be started with init_read_record_idx */ - if (used_index == MAX_KEY || (select && select->quick)) + if (query_plan.index == MAX_KEY || (select && select->quick)) { if (init_read_record(&info, thd, table, select, 0, 1, FALSE)) goto err; } else - init_read_record_idx(&info, thd, table, 1, used_index, reverse); + init_read_record_idx(&info, thd, table, 1, query_plan.index, reverse); thd_proc_info(thd, "Searching rows for update"); ha_rows tmp_limit= limit; @@ -610,6 +647,7 @@ int mysql_update(THD *thd, select= new SQL_SELECT; select->head=table; } + //psergey-todo: disable SHOW EXPLAIN because the plan was deleted? if (reinit_io_cache(&tempfile,READ_CACHE,0L,0,0)) error=1; /* purecov: inspected */ select->file=tempfile; // Read row ptrs from this file @@ -884,6 +922,7 @@ int mysql_update(THD *thd, if (!transactional_table && updated > 0) thd->transaction.stmt.modified_non_trans_table= TRUE; + thd->apc_target.disable(); //psergey-todo. end_read_record(&info); delete select; thd_proc_info(thd, "end"); @@ -962,6 +1001,27 @@ err: table->disable_keyread(); thd->abort_on_warning= 0; DBUG_RETURN(1); + +exit_without_my_ok: + thd->lex->upd_del_plan= &query_plan; + + select_send *result; + bool printed_anything; + if (!(result= new select_send())) + return 1; /* purecov: inspected */ + List dummy; /* note: looked in 5.6 and they too use a dummy list like this */ + result->prepare(dummy, &thd->lex->unit); + thd->send_explain_fields(result); + int err2= thd->lex->print_explain(result, 0 /* explain flags*/, &printed_anything); + + if (err2) + result->abort_result_set(); + else + result->send_eof(); + + delete select; + free_underlaid_joins(thd, select_lex); + DBUG_RETURN((error >= 0 || thd->is_error()) ? 1 : 0); } /* @@ -1381,23 +1441,37 @@ bool mysql_multi_update(THD *thd, multi_update **result) { bool res; + select_result *output; + bool explain= test(thd->lex->describe); DBUG_ENTER("mysql_multi_update"); - - if (!(*result= new multi_update(table_list, - &thd->lex->select_lex.leaf_tables, - fields, values, - handle_duplicates, ignore))) + + if (explain) { - DBUG_RETURN(TRUE); + /* Handle EXPLAIN UPDATE */ + if (!(output= new select_send()) || + thd->send_explain_fields(output)) + { + delete output; + DBUG_RETURN(TRUE); + } + select_lex->set_explain_type(FALSE); + *result= NULL; /* no multi_update object */ + } + else + { + if (!(*result= new multi_update(table_list, + &thd->lex->select_lex.leaf_tables, + fields, values, + handle_duplicates, ignore))) + { + DBUG_RETURN(TRUE); + } + output= *result; } thd->abort_on_warning= test(thd->variables.sql_mode & (MODE_STRICT_TRANS_TABLES | MODE_STRICT_ALL_TABLES)); -/* - psergey-explain-todo: - This is the place where EXPLAIN should be handled. -*/ List total_list; res= mysql_select(thd, &select_lex->ref_pointer_array, @@ -1407,12 +1481,20 @@ bool mysql_multi_update(THD *thd, (ORDER *)NULL, options | SELECT_NO_JOIN_CACHE | SELECT_NO_UNLOCK | OPTION_SETUP_TABLES_DONE, - *result, unit, select_lex); + output, unit, select_lex); DBUG_PRINT("info",("res: %d report_error: %d", res, (int) thd->is_error())); res|= thd->is_error(); if (unlikely(res)) (*result)->abort_result_set(); + else + { + if (explain) + { + output->send_eof(); + delete output; + } + } thd->abort_on_warning= 0; DBUG_RETURN(res); } -- cgit v1.2.1 From 9718b9763deeaa41008aeca31c24548e556401cc Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Mon, 27 May 2013 13:53:18 +0400 Subject: SHOW EXPLAIN DELETE, post merge fixes - Fix asserts, make sure that mysql_delete() operates on thd->apc_target correctly* in all kinds of special cases * - correctly means that one must switch it OFF iff it was switched ON. - Added a few asserts to catch similar errors. --- sql/my_apc.cc | 1 + sql/sql_parse.cc | 3 +++ sql/sql_update.cc | 7 +++++++ 3 files changed, 11 insertions(+) (limited to 'sql') diff --git a/sql/my_apc.cc b/sql/my_apc.cc index 3bad1331364..dcb1e3d99b1 100644 --- a/sql/my_apc.cc +++ b/sql/my_apc.cc @@ -70,6 +70,7 @@ void Apc_target::enable() void Apc_target::disable() { bool process= FALSE; + DBUG_ASSERT(enabled); mysql_mutex_lock(LOCK_thd_data_ptr); if (!(--enabled)) process= TRUE; diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc index 3b088616984..74981eb907b 100644 --- a/sql/sql_parse.cc +++ b/sql/sql_parse.cc @@ -807,7 +807,9 @@ bool do_command(THD *thd) my_net_set_read_timeout(net, thd->variables.net_read_timeout); DBUG_ASSERT(packet_length); + DBUG_ASSERT(!thd->apc_target.is_enabled()); return_value= dispatch_command(command, thd, packet+1, (uint) (packet_length-1)); + DBUG_ASSERT(!thd->apc_target.is_enabled()); out: DBUG_RETURN(return_value); @@ -1109,6 +1111,7 @@ bool dispatch_command(enum enum_server_command command, THD *thd, ulong length= (ulong)(packet_end - beginning_of_next_stmt); log_slow_statement(thd); + DBUG_ASSERT(!thd->apc_target.is_enabled()); /* Remove garbage at start of query */ while (length > 0 && my_isspace(thd->charset(), *beginning_of_next_stmt)) diff --git a/sql/sql_update.cc b/sql/sql_update.cc index ba3ee41909f..8b1b042e6df 100644 --- a/sql/sql_update.cc +++ b/sql/sql_update.cc @@ -279,6 +279,7 @@ int mysql_update(THD *thd, Update_plan query_plan; query_plan.index= MAX_KEY; query_plan.using_filesort= FALSE; + bool apc_target_enabled= false; // means was enabled *by code this function* DBUG_ENTER("mysql_update"); if (open_tables(thd, &table_list, &table_count, 0)) @@ -497,6 +498,7 @@ int mysql_update(THD *thd, goto exit_without_my_ok; thd->apc_target.enable(); + apc_target_enabled= true; DBUG_EXECUTE_IF("show_explain_probe_update_exec_start", dbug_serve_apcs(thd, 1);); @@ -923,6 +925,7 @@ int mysql_update(THD *thd, thd->transaction.stmt.modified_non_trans_table= TRUE; thd->apc_target.disable(); //psergey-todo. + apc_target_enabled= false; end_read_record(&info); delete select; thd_proc_info(thd, "end"); @@ -996,6 +999,9 @@ int mysql_update(THD *thd, DBUG_RETURN((error >= 0 || thd->is_error()) ? 1 : 0); err: + if (apc_target_enabled) + thd->apc_target.disable(); + delete select; free_underlaid_joins(thd, select_lex); table->disable_keyread(); @@ -1003,6 +1009,7 @@ err: DBUG_RETURN(1); exit_without_my_ok: + DBUG_ASSERT(!apc_target_enabled); thd->lex->upd_del_plan= &query_plan; select_send *result; -- cgit v1.2.1 From 03691a77718c781469b5675c6b03d6064255debb Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Mon, 17 Jun 2013 11:59:38 +0400 Subject: SHOW EXPLAIN UPDATE/DELETE - Introduce "Query Plan Footprints" (abbrev. QPFs) QPF is a part of query plan that is 1. sufficient to produce EXPLAIN output, 2. can be used to produce EXPLAIN output even after its subquery/union was executed and deleted 3. is cheap to save so that we can always save query plans - This patch doesn't fully address #2, we make/save strings for a number of EXPLAIN's columns. This will be fixed. --- sql/CMakeLists.txt | 1 + sql/handler.h | 3 +- sql/opt_qpf.cc | 417 ++++++++++++++++++++++++++++++++++++ sql/opt_qpf.h | 274 ++++++++++++++++++++++++ sql/sql_delete.cc | 5 +- sql/sql_lex.cc | 135 +++++++++++- sql/sql_lex.h | 12 +- sql/sql_parse.cc | 8 + sql/sql_select.cc | 608 ++++++++++++++++++++++++++++++++++++++++++++++++++++- sql/sql_select.h | 15 +- 10 files changed, 1464 insertions(+), 14 deletions(-) create mode 100644 sql/opt_qpf.cc create mode 100644 sql/opt_qpf.h (limited to 'sql') diff --git a/sql/CMakeLists.txt b/sql/CMakeLists.txt index 63e2df46bed..638c6cbca05 100644 --- a/sql/CMakeLists.txt +++ b/sql/CMakeLists.txt @@ -80,6 +80,7 @@ SET (SQL_SOURCE sql_reload.cc # added in MariaDB: + opt_qpf.h opt_qpf.cc sql_lifo_buffer.h sql_join_cache.h sql_join_cache.cc create_options.cc multi_range_read.cc opt_index_cond_pushdown.cc opt_subselect.cc diff --git a/sql/handler.h b/sql/handler.h index 18639b6a8a4..785b354deee 100644 --- a/sql/handler.h +++ b/sql/handler.h @@ -286,7 +286,8 @@ (yes, the sum is deliberately inaccurate) TODO remove the limit, use dynarrays */ -#define MAX_HA 15 +/*#define MAX_HA 15*/ +#define MAX_HA 32 /* Use this instead of 0 as the initial value for the slot number of diff --git a/sql/opt_qpf.cc b/sql/opt_qpf.cc new file mode 100644 index 00000000000..12aef844328 --- /dev/null +++ b/sql/opt_qpf.cc @@ -0,0 +1,417 @@ +/* + TODO MP AB copyright +*/ + +#ifdef USE_PRAGMA_IMPLEMENTATION +#pragma implementation // gcc: Class implementation +#endif + +#include "sql_priv.h" +#include "sql_select.h" + + +QPF_query::QPF_query() +{ + memset(&unions, 0, sizeof(unions)); + memset(&selects, 0, sizeof(selects)); +} + + +QPF_node *QPF_query::get_node(uint select_id) +{ + if (unions[select_id]) + return unions[select_id]; + else + return selects[select_id]; +} + + +QPF_select *QPF_query::get_select(uint select_id) +{ + return selects[select_id]; +} + + +void QPF_query::add_node(QPF_node *node) +{ + if (node->get_type() == QPF_node::QPF_UNION) + { + QPF_union *u= (QPF_union*)node; + unions[u->get_select_id()]= u; + } + else + { + QPF_select *sel= (QPF_select*)node; + if (sel->select_id == (int)UINT_MAX) + { + //TODO this is a "fake select" from a UNION. + DBUG_ASSERT(0); + } + else + selects[sel->select_id] = sel; + } +} + + +/* + The main entry point to print EXPLAIN of the entire query +*/ + +int QPF_query::print_explain(select_result_sink *output, + uint8 explain_flags) +{ + // Start with id=1 + QPF_node *node= get_node(1); + return node->print_explain(this, output, explain_flags); +} + + +void QPF_union::push_table_name(List *item_list) +{ +} + + +static void push_str(List *item_list, const char *str) +{ + item_list->push_back(new Item_string(str, + strlen(str), system_charset_info)); +} + + +static void push_string(List *item_list, String *str) +{ + item_list->push_back(new Item_string(str->ptr(), str->length(), + system_charset_info)); +} + + +int QPF_union::print_explain(QPF_query *query, select_result_sink *output, + uint8 explain_flags) +{ + // print all children, in order + for (int i= 0; i < (int) children.elements(); i++) + { + QPF_select *sel= query->get_select(children.at(i)); + sel->print_explain(query, output, explain_flags); + } + + /* Print a line with "UNION RESULT" */ + List item_list; + Item *item_null= new Item_null(); + + /* `id` column */ + item_list.push_back(item_null); + + /* `select_type` column */ + push_str(&item_list, fake_select_type); + + /* `table` column: something like "" */ + // + { + char table_name_buffer[SAFE_NAME_LEN]; + uint childno= 0; + uint len= 6, lastop= 0; + memcpy(table_name_buffer, STRING_WITH_LEN("= NAME_LEN) + { + memcpy(table_name_buffer + len, STRING_WITH_LEN("...>") + 1); + len+= 4; + } + else + { + len+= lastop; + table_name_buffer[len - 1]= '>'; // change ',' to '>' + } + const CHARSET_INFO *cs= system_charset_info; + item_list.push_back(new Item_string(table_name_buffer, len, cs)); + } + // + push_table_name(&item_list); + + /* `partitions` column */ + if (explain_flags & DESCRIBE_PARTITIONS) + item_list.push_back(item_null); + + /* `type` column */ + push_str(&item_list, join_type_str[JT_ALL]); + + /* `possible_keys` column */ + item_list.push_back(item_null); + + /* `key` */ + item_list.push_back(item_null); + + /* `key_len` */ + item_list.push_back(item_null); + + /* `ref` */ + item_list.push_back(item_null); + + /* `rows` */ + item_list.push_back(item_null); + + /* `filtered` */ + if (explain_flags & DESCRIBE_EXTENDED) + item_list.push_back(item_null); + + /* `Extra` */ + StringBuffer<256> extra_buf; + if (using_filesort) + { + extra_buf.append(STRING_WITH_LEN("Using filesort")); + } + const CHARSET_INFO *cs= system_charset_info; + item_list.push_back(new Item_string(extra_buf.ptr(), extra_buf.length(), cs)); + + if (output->send_data(item_list)) + return 1; + return 0; +} + + +int QPF_select::print_explain(QPF_query *query, select_result_sink *output, + uint8 explain_flags) +{ + if (message) + { + List item_list; + const CHARSET_INFO *cs= system_charset_info; + Item *item_null= new Item_null(); + + item_list.push_back(new Item_int((int32) select_id)); + item_list.push_back(new Item_string(select_type, + strlen(select_type), cs)); + for (uint i=0 ; i < 7; i++) + item_list.push_back(item_null); + if (explain_flags & DESCRIBE_PARTITIONS) + item_list.push_back(item_null); + if (explain_flags & DESCRIBE_EXTENDED) + item_list.push_back(item_null); + + item_list.push_back(new Item_string(message,strlen(message),cs)); + + if (output->send_data(item_list)) + return 1; + return 0; + } + else + { + bool using_tmp= using_temporary; + bool using_fs= using_filesort; + for (uint i=0; i< n_join_tabs; i++) + { + join_tabs[i]->print_explain(output, explain_flags, select_id, + select_type, using_tmp, using_fs); + if (i == 0) + { + /* + "Using temporary; Using filesort" should only be shown near the 1st + table + */ + using_tmp= false; + using_fs= false; + } + } + } + return 0; +} + + +int QPF_table_access::print_explain(select_result_sink *output, uint8 explain_flags, + uint select_id, const char *select_type, + bool using_temporary, bool using_filesort) +{ + List item_list; + Item *item_null= new Item_null(); + //const CHARSET_INFO *cs= system_charset_info; + + /* `id` column */ + item_list.push_back(new Item_int((int32) select_id)); + + /* `select_type` column */ + push_str(&item_list, select_type); + + /* `table` column */ + push_string(&item_list, &table_name); + + /* `partitions` column */ + if (explain_flags & DESCRIBE_PARTITIONS) + { + if (used_partitions_set) + { + push_string(&item_list, &used_partitions); + } + else + item_list.push_back(item_null); + } + + /* `type` column */ + push_str(&item_list, join_type_str[type]); + + /* `possible_keys` column */ + //push_str(item_list, "TODO"); + item_list.push_back(item_null); + + /* `key` */ + if (key_set) + push_string(&item_list, &key); + else + item_list.push_back(item_null); + + /* `key_len` */ + if (key_len_set) + push_string(&item_list, &key_len); + else + item_list.push_back(item_null); + + /* `ref` */ + if (ref_set) + push_string(&item_list, &ref); + else + item_list.push_back(item_null); + + /* `rows` */ + if (rows_set) + { + item_list.push_back(new Item_int((longlong) (ulonglong) rows, + MY_INT64_NUM_DECIMAL_DIGITS)); + } + else + item_list.push_back(item_null); + + /* `filtered` */ + if (explain_flags & DESCRIBE_EXTENDED) + { + if (filtered_set) + { + item_list.push_back(new Item_float(filtered, 2)); + } + else + item_list.push_back(item_null); + } + + /* `Extra` */ + StringBuffer<256> extra_buf; + bool first= true; + for (int i=0; i < (int)extra_tags.elements(); i++) + { + if (first) + first= false; + else + extra_buf.append(STRING_WITH_LEN("; ")); + append_tag_name(&extra_buf, extra_tags.at(i)); + } + + if (using_temporary) + { + if (first) + first= false; + else + extra_buf.append(STRING_WITH_LEN("; ")); + extra_buf.append(STRING_WITH_LEN("Using temporary")); + } + + if (using_filesort) + { + if (first) + first= false; + else + extra_buf.append(STRING_WITH_LEN("; ")); + extra_buf.append(STRING_WITH_LEN("Using filesort")); + } + + const CHARSET_INFO *cs= system_charset_info; + item_list.push_back(new Item_string(extra_buf.ptr(), extra_buf.length(), cs)); + + if (output->send_data(item_list)) + return 1; + + return 0; +} + + +const char * extra_tag_text[]= +{ + "ET_none", + "Using index condition", + "Using index condition(BKA)", + "Using ", //special + "Range checked for each record (index map: 0x", //special + "Using where with pushed condition", + "Using where", + "Not exists", + + "Using index", + "Full scan on NULL key", + "Skip_open_table", + "Open_frm_only", + "Open_full_table", + + "Scanned 0 databases", + "Scanned 1 database", + "Scanned all databases", + + "Using index for group-by", // Special? + + "USING MRR: DONT PRINT ME", // Special! + + "Distinct", + "LooseScan", + "Start temporary", + "End temporary", + "FirstMatch", //TODO: also handle special variant! + + "Using join buffer", // Special!, + + "const row not found", + "unique row not found", + "Impossible ON condition" +}; + + +void QPF_table_access::append_tag_name(String *str, enum Extra_tag tag) +{ + switch (tag) { + case ET_USING: + { + // quick select + str->append(STRING_WITH_LEN("Using ")); + str->append(quick_info); + break; + } + case ET_RANGE_CHECKED_FOR_EACH_RECORD: + { + /* 4 bits per 1 hex digit + terminating '\0' */ + char buf[MAX_KEY / 4 + 1]; + str->append(STRING_WITH_LEN("Range checked for each " + "record (index map: 0x")); + str->append(range_checked_map.print(buf)); + str->append(')'); + break; + } + case ET_USING_MRR: + { + str->append(mrr_type); + break; + } + case ET_USING_JOIN_BUFFER: + { + str->append(extra_tag_text[tag]); + str->append(join_buffer_type); + break; + } + default: + str->append(extra_tag_text[tag]); + } +} + + diff --git a/sql/opt_qpf.h b/sql/opt_qpf.h new file mode 100644 index 00000000000..86655f3ed3d --- /dev/null +++ b/sql/opt_qpf.h @@ -0,0 +1,274 @@ +/************************************************************************************** + + Query Plan Footprint (QPF) structures + + These structures + - Can be produced in-expensively from query plan. + - Store sufficient information to produce either a tabular or a json EXPLAIN + output + - Have methods that produce a tabular output. + +*************************************************************************************/ + +class QPF_query; + +/* + A node can be either a SELECT, or a UNION. +*/ +class QPF_node : public Sql_alloc +{ +public: + enum qpf_node_type {QPF_UNION, QPF_SELECT}; + + virtual enum qpf_node_type get_type()= 0; + virtual int print_explain(QPF_query *query, select_result_sink *output, + uint8 explain_flags)=0; + virtual ~QPF_node(){} +}; + + +/* + Nesting. + QPF_select may have children QPF_select-s. + (these can be FROM-subqueries, or subqueries from other clauses) + + As for unions, the standard approach is: + - UNION node can be where the select node can be; + - the union has a select that retrieves results from temptable (a special + kind of child) + - and it has regular children selects that are merged into the union. + +*/ + +class QPF_table_access; + +class QPF_select : public QPF_node +{ + /*Construction interface */ +public: + enum qpf_node_type get_type() { return QPF_SELECT; } + +#if 0 + /* Constructs a finished degenerate join plan */ + QPF_select(int select_id_arg, const char *select_type_arg, const char* msg) : + select_id(select_id_arg), + select_type(select_type_arg), + message(msg), + join_tabs(NULL), n_join_tabs(0) + {} + + /* Constructs an un-finished, non degenerate join plan. */ + QPF_select(int select_id_arg, const char *select_type_arg) : + select_id(select_id_arg), + select_type(select_type_arg), + message(NULL), + join_tabs(NULL), n_join_tabs(0) + {} +#endif + QPF_select() : + message(NULL), join_tabs(NULL), + using_temporary(false), using_filesort(false) + {} + + bool add_table(QPF_table_access *tab) + { + if (!join_tabs) + { + join_tabs= (QPF_table_access**) malloc(sizeof(QPF_table_access*) * MAX_TABLES); + n_join_tabs= 0; + } + join_tabs[n_join_tabs++]= tab; + return false; + } + +public: + int select_id; /* -1 means NULL. */ + const char *select_type; + + /* + If message != NULL, this is a degenerate join plan, and all subsequent + members have no info + */ + const char *message; + + /* + According to the discussion: this should be an array of "table + descriptors". + + As for SJ-Materialization. Start_materialize/end_materialize markers? + */ + QPF_table_access** join_tabs; + uint n_join_tabs; + + /* Global join attributes. In tabular form, they are printed on the first row */ + bool using_temporary; + bool using_filesort; + + void print_tabular(select_result_sink *output, uint8 explain_flags//, + //bool *printed_anything + ); + + int print_explain(QPF_query *query, select_result_sink *output, + uint8 explain_flags); +}; + + +class QPF_union : public QPF_node +{ +public: + enum qpf_node_type get_type() { return QPF_UNION; } + + int get_select_id() + { + DBUG_ASSERT(children.elements() > 0); + return children.at(0); + } + // This has QPF_select children + Dynamic_array children; + + void add_select(int select_no) + { + children.append(select_no); + } + void push_table_name(List *item_list); + int print_explain(QPF_query *query, select_result_sink *output, + uint8 explain_flags); + + const char *fake_select_type; + bool using_filesort; +}; + + +/* + This is the whole query. +*/ + +class QPF_query +{ +public: + QPF_query(); + void add_node(QPF_node *node); + int print_explain(select_result_sink *output, uint8 explain_flags); + + /* This will return a select, or a union */ + QPF_node *get_node(uint select_id); + + /* This will return a select (even if there is a union with this id) */ + QPF_select *get_select(uint select_id); + +private: + QPF_union *unions[MAX_TABLES]; + QPF_select *selects[MAX_TABLES]; +}; + + +enum Extra_tag +{ + ET_none= 0, /* not-a-tag */ + ET_USING_INDEX_CONDITION, + ET_USING_INDEX_CONDITION_BKA, + ET_USING, /* For quick selects of various kinds */ + ET_RANGE_CHECKED_FOR_EACH_RECORD, + ET_USING_WHERE_WITH_PUSHED_CONDITION, + ET_USING_WHERE, + ET_NOT_EXISTS, + + ET_USING_INDEX, + ET_FULL_SCAN_ON_NULL_KEY, + ET_SKIP_OPEN_TABLE, + ET_OPEN_FRM_ONLY, + ET_OPEN_FULL_TABLE, + + ET_SCANNED_0_DATABASES, + ET_SCANNED_1_DATABASE, + ET_SCANNED_ALL_DATABASES, + + ET_USING_INDEX_FOR_GROUP_BY, + + ET_USING_MRR, // does not print "Using mrr". + + ET_DISTINCT, + ET_LOOSESCAN, + ET_START_TEMPORARY, + ET_END_TEMPORARY, + ET_FIRST_MATCH, + + ET_USING_JOIN_BUFFER, + + ET_CONST_ROW_NOT_FOUND, + ET_UNIQUE_ROW_NOT_FOUND, + ET_IMPOSSIBLE_ON_CONDITION, + + ET_total +}; + + +class QPF_table_access +{ +public: + void push_extra(enum Extra_tag extra_tag); + + /* Internals */ +public: + /* id and 'select_type' are cared-of by the parent QPF_select */ + TABLE *table; + StringBuffer<256> table_name; + + enum join_type type; + + StringBuffer<256> used_partitions; + bool used_partitions_set; + + key_map possible_keys; + + uint key_no; + uint key_length; + + Dynamic_array extra_tags; + + //temporary: + StringBuffer<256> key; + StringBuffer<256> key_len; + StringBuffer<256> ref; + bool key_set; + bool key_len_set; + bool ref_set; + + bool rows_set; + ha_rows rows; + + double filtered; + bool filtered_set; + + /* Various stuff for 'Extra' column*/ + uint join_cache_level; + + // Valid if ET_USING tag is present + StringBuffer<256> quick_info; + + // Valid if ET_USING_INDEX_FOR_GROUP_BY is present + StringBuffer<256> loose_scan_type; + + // valid with ET_RANGE_CHECKED_FOR_EACH_RECORD + key_map range_checked_map; + + // valid with ET_USING_MRR + StringBuffer <256> mrr_type; + + // valid with ET_USING_JOIN_BUFFER + StringBuffer <256> join_buffer_type; + + TABLE *firstmatch_table; + + int print_explain(select_result_sink *output, uint8 explain_flags, + uint select_id, const char *select_type, + bool using_temporary, bool using_filesort); +private: + void append_tag_name(String *str, enum Extra_tag tag); +}; + +// Update_plan and Delete_plan belong to this kind of structures, too. + +// TODO: should Update_plan inherit from QPF_table_access? + + diff --git a/sql/sql_delete.cc b/sql/sql_delete.cc index df659871a64..390d9e3945a 100644 --- a/sql/sql_delete.cc +++ b/sql/sql_delete.cc @@ -169,7 +169,9 @@ int Update_plan::print_explain(select_result_sink *output, uint8 explain_flags, extra_str.c_ptr()); *printed_anything= true; - + /* + psergey-todo: handle all this through saving QPF. + for (SELECT_LEX_UNIT *unit= select_lex->first_inner_unit(); unit; unit= unit->next_unit()) @@ -177,6 +179,7 @@ int Update_plan::print_explain(select_result_sink *output, uint8 explain_flags, if (unit->print_explain(output, explain_flags, printed_anything)) return 1; } + */ return 0; } diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc index 1d2490666ea..b2d4ca13823 100644 --- a/sql/sql_lex.cc +++ b/sql/sql_lex.cc @@ -4172,6 +4172,7 @@ bool st_select_lex::is_merged_child_of(st_select_lex *ancestor) return all_merged; } + int LEX::print_explain(select_result_sink *output, uint8 explain_flags, bool *printed_anything) { @@ -4180,11 +4181,87 @@ int LEX::print_explain(select_result_sink *output, uint8 explain_flags, upd_del_plan->print_explain(output, explain_flags, printed_anything); return 0; } - int res= unit.print_explain(output, explain_flags, printed_anything); - return res; + //int res= unit.print_explain(output, explain_flags, printed_anything); + + //psergey-todo: here, we should make Query Plan Footprint, and then produce + // an EXPLAIN output from it. + /* + The new, QueryPlanFootprint way: + */ + QPF_query qpf; + unit.save_qpf(&qpf); + //return res; + return 0; } +void st_select_lex::save_qpf(QPF_query *output) +{ + int res; + if (join && join->have_query_plan == JOIN::QEP_AVAILABLE) + { + /* + There is a number of reasons join can be marked as degenerate, so all + three conditions below can happen simultaneously, or individually: + */ + if (!join->table_count || !join->tables_list || join->zero_result_cause) + { + /* It's a degenerate join */ + const char *cause= join->zero_result_cause ? join-> zero_result_cause : + "No tables used"; + res= join->save_qpf(output, FALSE, FALSE, FALSE, cause); + } + else + { + join->save_qpf(output, join->need_tmp, // need_tmp_table + !join->skip_sort_order && !join->no_order && + (join->order || join->group_list), // bool need_order + join->select_distinct, // bool distinct + NULL); //const char *message + } + if (res) + goto err; + + for (SELECT_LEX_UNIT *unit= join->select_lex->first_inner_unit(); + unit; + unit= unit->next_unit()) + { + /* + Display subqueries only if they are not parts of eliminated WHERE/ON + clauses. + */ + if (!(unit->item && unit->item->eliminated)) + { + unit->save_qpf(output); + } + } + } + else + { + const char *msg; + if (!join) + DBUG_ASSERT(0); /* Seems not to be possible */ + + /* Not printing anything useful, don't touch *printed_anything here */ + if (join->have_query_plan == JOIN::QEP_NOT_PRESENT_YET) + msg= "Not yet optimized"; + else + { + DBUG_ASSERT(join->have_query_plan == JOIN::QEP_DELETED); + msg= "Query plan already deleted"; + } + set_explain_type(TRUE/* on_the_fly */); + QPF_select *qp_sel= new QPF_select; + qp_sel->select_id= select_number; + qp_sel->select_type= type; + qp_sel->message= msg; + output->add_node(qp_sel); + } +err: + return ;//res; +} + +#if 0 int st_select_lex::print_explain(select_result_sink *output, uint8 explain_flags, bool *printed_anything) @@ -4253,8 +4330,60 @@ int st_select_lex::print_explain(select_result_sink *output, err: return res; } +#endif + + +int st_select_lex_unit::save_qpf(QPF_query *output) +{ + //int res= 0; + SELECT_LEX *first= first_select(); + + QPF_union *qpfu= new QPF_union; + /* + TODO: The following code should be eliminated. If we have a capability to + save Query Plan Footprints, we should just save them, and never need to + print "query plan already deleted". + */ + if (first && !first->next_select() && !first->join) + { + /* + If there is only one child, 'first', and it has join==NULL, emit "not in + EXPLAIN state" error. + */ + const char *msg="Query plan already deleted"; + first->set_explain_type(TRUE/* on_the_fly */); + + QPF_select *qp_sel= new QPF_select; + qp_sel->select_id= first->select_number; + qp_sel->select_type= first->type; + qp_sel->message= msg; + output->add_node(qp_sel); + qpfu->add_select(qp_sel->select_id); + return 0; + } + + for (SELECT_LEX *sl= first; sl; sl= sl->next_select()) + { + sl->save_qpf(output); + qpfu->add_select(sl->select_number); + } + // Save the UNION node + output->add_node(qpfu); +#if 0 + /* Note: fake_select_lex->join may be NULL or non-NULL at this point */ + if (fake_select_lex) + { + res= print_fake_select_lex_join(output, TRUE /* on the fly */, + fake_select_lex, explain_flags); + } + return res; +#endif + return 0; +} + +#if 0 int st_select_lex_unit::print_explain(select_result_sink *output, uint8 explain_flags, bool *printed_anything) { @@ -4288,7 +4417,7 @@ int st_select_lex_unit::print_explain(select_result_sink *output, } return res; } - +#endif /** A routine used by the parser to decide whether we are specifying a full diff --git a/sql/sql_lex.h b/sql/sql_lex.h index 2b075b77000..d2a8b59a593 100644 --- a/sql/sql_lex.h +++ b/sql/sql_lex.h @@ -617,7 +617,7 @@ class select_result; class JOIN; class select_union; class Procedure; - +class QPF_query; class st_select_lex_unit: public st_select_lex_node { protected: @@ -728,8 +728,11 @@ public: friend int subselect_union_engine::exec(); List *get_unit_column_types(); +#if 0 int print_explain(select_result_sink *output, uint8 explain_flags, bool *printed_anything); +#endif + int save_qpf(QPF_query *output); }; typedef class st_select_lex_unit SELECT_LEX_UNIT; @@ -1048,8 +1051,11 @@ public: bool save_prep_leaf_tables(THD *thd); bool is_merged_child_of(st_select_lex *ancestor); +#if 0 int print_explain(select_result_sink *output, uint8 explain_flags, bool *printed_anything); +#endif + void save_qpf(QPF_query *output); /* For MODE_ONLY_FULL_GROUP_BY we need to maintain two flags: - Non-aggregated fields are used in this select. @@ -2360,6 +2366,8 @@ class SQL_SELECT; /* Query plan of a single-table UPDATE. (This is actually a plan for single-table DELETE also) + + TODO: this should be a query plan footprint, not a query plan. */ class Update_plan { @@ -2411,6 +2419,7 @@ public: }; +class QPF_query; /* The state of the lex parsing. This is saved in the THD struct */ struct LEX: public Query_tables_list @@ -2424,6 +2433,7 @@ struct LEX: public Query_tables_list /* For single-table DELETE: its query plan */ Update_plan *upd_del_plan; + QPF_query *query_plan_footprint; char *length,*dec,*change; LEX_STRING name; diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc index 74981eb907b..aab26e72a65 100644 --- a/sql/sql_parse.cc +++ b/sql/sql_parse.cc @@ -4811,7 +4811,15 @@ static bool execute_sqlcom_select(THD *thd, TABLE_LIST *all_tables) if (!(result= new select_send())) return 1; /* purecov: inspected */ thd->send_explain_fields(result); + thd->lex->query_plan_footprint= new QPF_query; res= mysql_explain_union(thd, &thd->lex->unit, result); + + thd->lex->query_plan_footprint->print_explain(result, thd->lex->describe); + + //psergey-todo: here, produce the EXPLAIN output. + // mysql_explain_union() itself is only responsible for calling + // optimize() for all parts of the query. + /* The code which prints the extended description is not robust against malformed queries, so skip it if we have an error. diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 74df58db214..45090a2cec5 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -3856,7 +3856,7 @@ make_join_statistics(JOIN *join, List &tables_list, if (*s->on_expr_ref) { /* Generate empty row */ - s->info= "Impossible ON condition"; + s->info= ET_IMPOSSIBLE_ON_CONDITION; found_const_table_map|= s->table->map; s->type= JT_CONST; mark_as_null_row(s->table); // All fields are NULL @@ -17219,7 +17219,7 @@ join_read_const_table(JOIN_TAB *tab, POSITION *pos) { if ((error=join_read_system(tab))) { // Info for DESCRIBE - tab->info="const row not found"; + tab->info= ET_CONST_ROW_NOT_FOUND; /* Mark for EXPLAIN that the row was not found */ pos->records_read=0.0; pos->ref_depend_map= 0; @@ -17245,7 +17245,7 @@ join_read_const_table(JOIN_TAB *tab, POSITION *pos) table->disable_keyread(); if (error) { - tab->info="unique row not found"; + tab->info= ET_UNIQUE_ROW_NOT_FOUND; /* Mark for EXPLAIN that the row was not found */ pos->records_read=0.0; pos->ref_depend_map= 0; @@ -22321,8 +22321,11 @@ void explain_append_mrr_info(QUICK_RANGE_SELECT *quick, String *res) selects) @param on_the_fly TRUE <=> we're being executed on-the-fly, so don't make modifications to any select's data structures -*/ + psergey-todo: should this produce a data structure with a query plan? Or, the + data structure with the query plan should be produced in any way? +*/ +#if 0 int JOIN::print_explain(select_result_sink *result, uint8 explain_flags, bool on_the_fly, bool need_tmp_table, bool need_order, @@ -22381,6 +22384,7 @@ int JOIN::print_explain(select_result_sink *result, uint8 explain_flags, bool printing_materialize_nest= FALSE; uint select_id= join->select_lex->select_number; + JOIN_TAB* const first_top_tab= first_breadth_first_tab(join, WALK_OPTIMIZATION_TABS); for (JOIN_TAB *tab= first_breadth_first_tab(join, WALK_OPTIMIZATION_TABS); tab; @@ -22392,7 +22396,7 @@ int JOIN::print_explain(select_result_sink *result, uint8 explain_flags, select_id= first_sibling->emb_sj_nest->sj_subq_pred->get_identifier(); printing_materialize_nest= TRUE; } - + TABLE *table=tab->table; TABLE_LIST *table_list= tab->table->pos_in_table_list; char buff[512]; @@ -22672,7 +22676,23 @@ int JOIN::print_explain(select_result_sink *result, uint8 explain_flags, key_read=1; if (tab->info) - item_list.push_back(new Item_string(tab->info,strlen(tab->info),cs)); + { + const char *reason; + switch (tab->info) { + case ET_CONST_ROW_NOT_FOUND: + reason= "const row not found"; + break; + case ET_UNIQUE_ROW_NOT_FOUND: + reason= "unique row not found"; + break; + case ET_IMPOSSIBLE_ON_CONDITION: + reason= "Impossible ON condition"; + break; + default: + DBUG_ASSERT(0); + } + item_list.push_back(new Item_string(reason,strlen(reason),cs)); + } else if (tab->packed_info & TAB_INFO_HAVE_VALUE) { if (tab->packed_info & TAB_INFO_USING_INDEX) @@ -22876,6 +22896,577 @@ int JOIN::print_explain(select_result_sink *result, uint8 explain_flags, } DBUG_RETURN(error); } +#endif +///////////////////////////////////////////////////////////////////////////////////////////////// +void QPF_table_access::push_extra(enum Extra_tag extra_tag) +{ + extra_tags.append(extra_tag); +} + + +/* + Save Query Plan Footprint + push_extra + + P +*/ + +int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, + bool distinct, const char *message) +{ + QPF_select *qp_sel; + const bool on_the_fly= true; + + JOIN *join= this; /* Legacy: this code used to be a non-member function */ + THD *thd=join->thd; + const CHARSET_INFO *cs= system_charset_info; + int quick_type; + int error= 0; + DBUG_ENTER("JOIN::print_explain"); + DBUG_PRINT("info", ("Select 0x%lx, type %s, message %s", + (ulong)join->select_lex, join->select_lex->type, + message ? message : "NULL")); + DBUG_ASSERT(have_query_plan == QEP_AVAILABLE); + /* Don't log this into the slow query log */ + + qp_sel= new QPF_select; + + /* + NOTE: the number/types of items pushed into item_list must be in sync with + EXPLAIN column types as they're "defined" in THD::send_explain_fields() + */ + if (message) + { + join->select_lex->set_explain_type(on_the_fly); + + qp_sel->select_id= join->select_lex->select_number; + qp_sel->select_type= join->select_lex->type; + qp_sel->message= message; + /* Setting qp_sel->message means that all other members are invalid */ + output->add_node(qp_sel); + } + else if (join->select_lex == join->unit->fake_select_lex) + { + select_lex->set_explain_type(on_the_fly); + QPF_union *qp_union= new QPF_union; + + SELECT_LEX *child; + for (child= select_lex->master_unit()->first_select(); child; + child=child->next_select()) + { + qp_union->add_select(child->select_number); + } + + qp_union->fake_select_type= select_lex->type; + qp_union->using_filesort= + test(select_lex->master_unit()->global_parameters->order_list.first); + + output->add_node(qp_union); + } + else if (!join->select_lex->master_unit()->derived || + join->select_lex->master_unit()->derived->is_materialized_derived()) + { + table_map used_tables=0; + + if (on_the_fly) + join->select_lex->set_explain_type(on_the_fly); + + bool printing_materialize_nest= FALSE; + uint select_id= join->select_lex->select_number; + + qp_sel->select_id= join->select_lex->select_number; + qp_sel->select_type= join->select_lex->type; + + JOIN_TAB* const first_top_tab= first_breadth_first_tab(join, WALK_OPTIMIZATION_TABS); + + for (JOIN_TAB *tab= first_breadth_first_tab(join, WALK_OPTIMIZATION_TABS); tab; + tab= next_breadth_first_tab(join, WALK_OPTIMIZATION_TABS, tab)) + { + QPF_table_access *qpt= new QPF_table_access; + qp_sel->add_table(qpt); + + if (tab->bush_root_tab) + { + JOIN_TAB *first_sibling= tab->bush_root_tab->bush_children->start; + select_id= first_sibling->emb_sj_nest->sj_subq_pred->get_identifier(); + printing_materialize_nest= TRUE; + } + + TABLE *table=tab->table; + TABLE_LIST *table_list= tab->table->pos_in_table_list; + char buff2[512], buff3[512], buff4[512]; + char keylen_str_buf[64]; + my_bool key_read; + char table_name_buffer[SAFE_NAME_LEN]; + String tmp2(buff2,sizeof(buff2),cs); + String tmp3(buff3,sizeof(buff3),cs); + String tmp4(buff4,sizeof(buff4),cs); + char hash_key_prefix[]= "#hash#"; + KEY *key_info= 0; + uint key_len= 0; + bool is_hj= tab->type == JT_HASH || tab->type ==JT_HASH_NEXT; + + tmp2.length(0); + tmp3.length(0); + tmp4.length(0); + quick_type= -1; + QUICK_SELECT_I *quick= NULL; + JOIN_TAB *saved_join_tab= NULL; + + /* Don't show eliminated tables */ + if (table->map & join->eliminated_tables) + { + used_tables|=table->map; + continue; + } + + + if (join->table_access_tabs == join->join_tab && + tab == (first_top_tab + join->const_tables) && pre_sort_join_tab) + { + saved_join_tab= tab; + tab= pre_sort_join_tab; + } + + /* id */ + qp_sel->select_id= select_id; + + /* select_type */ + //const char* stype= printing_materialize_nest? "MATERIALIZED" : + // join->select_lex->type; + //item_list.push_back(new Item_string(stype, strlen(stype), cs)); + qp_sel->select_type= join->select_lex->type; + + /* table */ + if (table->derived_select_number) + { + /* Derived table name generation */ + int len= my_snprintf(table_name_buffer, sizeof(table_name_buffer)-1, + "", + table->derived_select_number); + qpt->table_name.set(table_name_buffer, len, cs); + } + else if (tab->bush_children) + { + JOIN_TAB *ctab= tab->bush_children->start; + /* table */ + int len= my_snprintf(table_name_buffer, + sizeof(table_name_buffer)-1, + "", + ctab->emb_sj_nest->sj_subq_pred->get_identifier()); + qpt->table_name.set(table_name_buffer, len, cs); + } + else + { + TABLE_LIST *real_table= table->pos_in_table_list; + qpt->table_name.set(real_table->alias, strlen(real_table->alias), cs); + } + + /* "partitions" column */ + { +#ifdef WITH_PARTITION_STORAGE_ENGINE + partition_info *part_info; + if (!table->derived_select_number && + (part_info= table->part_info)) + { + make_used_partitions_str(part_info, &qpt->used_partitions); + qpt->used_partitions_set= true; + } + else + qpt->used_partitions_set= false; +#else + /* just produce empty column if partitioning is not compiled in */ + qpt->used_partitions_set= false; +#endif + } + + /* "type" column */ + enum join_type tab_type= tab->type; + if ((tab->type == JT_ALL || tab->type == JT_HASH) && + tab->select && tab->select->quick && tab->use_quick != 2) + { + quick= tab->select->quick; + quick_type= tab->select->quick->get_type(); + if ((quick_type == QUICK_SELECT_I::QS_TYPE_INDEX_MERGE) || + (quick_type == QUICK_SELECT_I::QS_TYPE_INDEX_INTERSECT) || + (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_INTERSECT) || + (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_UNION)) + tab_type= tab->type == JT_ALL ? JT_INDEX_MERGE : JT_HASH_INDEX_MERGE; + else + tab_type= tab->type == JT_ALL ? JT_RANGE : JT_HASH_RANGE; + } + qpt->type= tab_type; + + /* Build "possible_keys" value */ + qpt->possible_keys= tab->keys; + + /* Build "key", "key_len", and "ref" */ + + // tmp2 holds key_name + // tmp3 holds key_length + // tmp4 holds ref? + if (tab_type == JT_NEXT) + { + key_info= table->key_info+tab->index; + key_len= key_info->key_length; + } + else if (tab->ref.key_parts) + { + key_info= tab->get_keyinfo_by_key_no(tab->ref.key); + key_len= tab->ref.key_length; + } + + if (key_info) + { + register uint length; + if (is_hj) + tmp2.append(hash_key_prefix, strlen(hash_key_prefix), cs); + tmp2.append(key_info->name, strlen(key_info->name), cs); + length= (longlong10_to_str(key_len, keylen_str_buf, 10) - + keylen_str_buf); + tmp3.append(keylen_str_buf, length, cs); + if (tab->ref.key_parts && tab_type != JT_FT) + { + store_key **ref=tab->ref.key_copy; + for (uint kp= 0; kp < tab->ref.key_parts; kp++) + { + if (tmp4.length()) + tmp4.append(','); + + if ((key_part_map(1) << kp) & tab->ref.const_ref_part_map) + tmp4.append("const"); + else + { + tmp4.append((*ref)->name(), strlen((*ref)->name()), cs); + ref++; + } + } + } + } + + if (is_hj && tab_type != JT_HASH) + { + tmp2.append(':'); + tmp3.append(':'); + } + + if (tab_type == JT_HASH_NEXT) + { + register uint length; + key_info= table->key_info+tab->index; + key_len= key_info->key_length; + tmp2.append(key_info->name, strlen(key_info->name), cs); + length= (longlong10_to_str(key_len, keylen_str_buf, 10) - + keylen_str_buf); + tmp3.append(keylen_str_buf, length, cs); + } + + if (tab->type != JT_CONST && tab->select && quick) + tab->select->quick->add_keys_and_lengths(&tmp2, &tmp3); + + if (key_info || (tab->select && quick)) + { + if (tmp2.length()) + { + qpt->key.copy(tmp2); + qpt->key_set= true; + } + else + qpt->key_set= false; + + if (tmp3.length()) + { + qpt->key_len.copy(tmp3); + qpt->key_len_set= true; + } + else + qpt->key_len_set= false; + + if (key_info && tab_type != JT_NEXT) + { + qpt->ref.copy(tmp4); + qpt->ref_set= true; + } + else + qpt->ref_set= false; + } + else + { + if (table_list && /* SJM bushes don't have table_list */ + table_list->schema_table && + table_list->schema_table->i_s_requested_object & OPTIMIZE_I_S_TABLE) + { + const char *tmp_buff; + int f_idx; + if (table_list->has_db_lookup_value) + { + f_idx= table_list->schema_table->idx_field1; + tmp_buff= table_list->schema_table->fields_info[f_idx].field_name; + tmp2.append(tmp_buff, strlen(tmp_buff), cs); + } + if (table_list->has_table_lookup_value) + { + if (table_list->has_db_lookup_value) + tmp2.append(','); + f_idx= table_list->schema_table->idx_field2; + tmp_buff= table_list->schema_table->fields_info[f_idx].field_name; + tmp2.append(tmp_buff, strlen(tmp_buff), cs); + } + if (tmp2.length()) + { + qpt->key.copy(tmp2); + qpt->key_set= true; + } + else + qpt->key_set= false; + } + else + qpt->key_set= false; + + qpt->key_len_set= false; + qpt->ref_set= false; + } + + /* "rows" */ + + if (table_list /* SJM bushes don't have table_list */ && + table_list->schema_table) + { + /* I_S tables have rows=extra=NULL */ + qpt->rows_set= false; + qpt->filtered_set= false; + } + else + { + ha_rows examined_rows= tab->get_examined_rows(); + + qpt->rows_set= true; + qpt->rows= examined_rows; + + /* "filtered" */ + float f= 0.0; + if (examined_rows) + { + double pushdown_cond_selectivity= tab->cond_selectivity; + if (pushdown_cond_selectivity == 1.0) + f= (float) (100.0 * tab->records_read / examined_rows); + else + f= (float) (100.0 * pushdown_cond_selectivity); + } + set_if_smaller(f, 100.0); + qpt->filtered_set= true; + qpt->filtered= f; + } + + /* Build "Extra" field and save it */ + key_read=table->key_read; + if ((tab_type == JT_NEXT || tab_type == JT_CONST) && + table->covering_keys.is_set(tab->index)) + key_read=1; + if (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_INTERSECT && + !((QUICK_ROR_INTERSECT_SELECT*)quick)->need_to_fetch_row) + key_read=1; + + if (tab->info) + { + qpt->push_extra(tab->info); + } + else if (tab->packed_info & TAB_INFO_HAVE_VALUE) + { + if (tab->packed_info & TAB_INFO_USING_INDEX) + qpt->push_extra(ET_USING_INDEX); + if (tab->packed_info & TAB_INFO_USING_WHERE) + qpt->push_extra(ET_USING_WHERE); + if (tab->packed_info & TAB_INFO_FULL_SCAN_ON_NULL) + qpt->push_extra(ET_FULL_SCAN_ON_NULL_KEY); + } + else + { + uint keyno= MAX_KEY; + if (tab->ref.key_parts) + keyno= tab->ref.key; + else if (tab->select && quick) + keyno = quick->index; + + if (keyno != MAX_KEY && keyno == table->file->pushed_idx_cond_keyno && + table->file->pushed_idx_cond) + qpt->push_extra(ET_USING_INDEX_CONDITION); + else if (tab->cache_idx_cond) + qpt->push_extra(ET_USING_INDEX_CONDITION_BKA); + + if (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_UNION || + quick_type == QUICK_SELECT_I::QS_TYPE_ROR_INTERSECT || + quick_type == QUICK_SELECT_I::QS_TYPE_INDEX_INTERSECT || + quick_type == QUICK_SELECT_I::QS_TYPE_INDEX_MERGE) + { + qpt->push_extra(ET_USING); + tab->select->quick->add_info_string(&qpt->quick_info); + } + if (tab->select) + { + if (tab->use_quick == 2) + { + qpt->push_extra(ET_RANGE_CHECKED_FOR_EACH_RECORD); + qpt->range_checked_map= tab->keys; + } + else if (tab->select->cond) + { + const COND *pushed_cond= tab->table->file->pushed_cond; + + if (((thd->variables.optimizer_switch & + OPTIMIZER_SWITCH_ENGINE_CONDITION_PUSHDOWN) || + (tab->table->file->ha_table_flags() & + HA_MUST_USE_TABLE_CONDITION_PUSHDOWN)) && + pushed_cond) + { + qpt->push_extra(ET_USING_WHERE_WITH_PUSHED_CONDITION); + /* + psergey-todo: what to do? This was useful with NDB only. + + if (explain_flags & DESCRIBE_EXTENDED) + { + extra.append(STRING_WITH_LEN(": ")); + ((COND *)pushed_cond)->print(&extra, QT_ORDINARY); + } + */ + } + else + qpt->push_extra(ET_USING_WHERE); + } + } + if (table_list /* SJM bushes don't have table_list */ && + table_list->schema_table && + table_list->schema_table->i_s_requested_object & OPTIMIZE_I_S_TABLE) + { + if (!table_list->table_open_method) + qpt->push_extra(ET_SKIP_OPEN_TABLE); + else if (table_list->table_open_method == OPEN_FRM_ONLY) + qpt->push_extra(ET_OPEN_FRM_ONLY); + else + qpt->push_extra(ET_OPEN_FULL_TABLE); + /* psergey-note: the following has a bug.*/ + if (table_list->has_db_lookup_value && + table_list->has_table_lookup_value) + qpt->push_extra(ET_SCANNED_0_DATABASES); + else if (table_list->has_db_lookup_value || + table_list->has_table_lookup_value) + qpt->push_extra(ET_SCANNED_1_DATABASE); + else + qpt->push_extra(ET_SCANNED_ALL_DATABASES); + } + if (key_read) + { + if (quick_type == QUICK_SELECT_I::QS_TYPE_GROUP_MIN_MAX) + { + QUICK_GROUP_MIN_MAX_SELECT *qgs= + (QUICK_GROUP_MIN_MAX_SELECT *) tab->select->quick; + qpt->push_extra(ET_USING_INDEX_FOR_GROUP_BY); + qgs->append_loose_scan_type(&qpt->loose_scan_type); + } + else + qpt->push_extra(ET_USING_INDEX); + } + if (table->reginfo.not_exists_optimize) + qpt->push_extra(ET_NOT_EXISTS); + + /* + if (quick_type == QUICK_SELECT_I::QS_TYPE_RANGE && + !(((QUICK_RANGE_SELECT*)(tab->select->quick))->mrr_flags & + HA_MRR_USE_DEFAULT_IMPL)) + { + extra.append(STRING_WITH_LEN("; Using MRR")); + } + */ + if (quick_type == QUICK_SELECT_I::QS_TYPE_RANGE) + { + qpt->push_extra(ET_USING_MRR); + explain_append_mrr_info((QUICK_RANGE_SELECT*)(tab->select->quick), + &qpt->mrr_type); + } + + if (need_tmp_table) + { + need_tmp_table=0; + qp_sel->using_temporary= true; + ///extra.append(STRING_WITH_LEN("; Using temporary")); + } + if (need_order) + { + need_order=0; + qp_sel->using_filesort= true; + ///extra.append(STRING_WITH_LEN("; Using filesort")); + } + if (distinct & test_all_bits(used_tables, + join->select_list_used_tables)) + qpt->push_extra(ET_DISTINCT); + if (tab->loosescan_match_tab) + { + qpt->push_extra(ET_LOOSESCAN); + } + + if (tab->first_weedout_table) + qpt->push_extra(ET_START_TEMPORARY); + if (tab->check_weed_out_table) + qpt->push_extra(ET_END_TEMPORARY); + else if (tab->do_firstmatch) + { + if (tab->do_firstmatch == /*join->join_tab*/ first_top_tab - 1) + qpt->push_extra(ET_FIRST_MATCH); + else + { + qpt->push_extra(ET_FIRST_MATCH); + //TABLE *prev_table=tab->do_firstmatch->table; + /* + TODO: qpt->firstmatch_table... + This must be a reference to another QPF element. Or, its index. + */ +#if 0 + extra.append(STRING_WITH_LEN("; FirstMatch(")); + if (prev_table->derived_select_number) + { + char namebuf[NAME_LEN]; + /* Derived table name generation */ + int len= my_snprintf(namebuf, sizeof(namebuf)-1, + "", + prev_table->derived_select_number); + extra.append(namebuf, len); + } + else + extra.append(prev_table->pos_in_table_list->alias); + extra.append(STRING_WITH_LEN(")")); +#endif + } + } + + for (uint part= 0; part < tab->ref.key_parts; part++) + { + if (tab->ref.cond_guards[part]) + { + qpt->push_extra(ET_FULL_SCAN_ON_NULL_KEY); + break; + } + } + + if (tab->cache) + { + qpt->push_extra(ET_USING_JOIN_BUFFER); + tab->cache->print_explain_comment(&qpt->join_buffer_type); + } + + } + + if (saved_join_tab) + tab= saved_join_tab; + + // For next iteration + used_tables|=table->map; + } + output->add_node(qp_sel); + } + DBUG_RETURN(error); +} + +////////////////////////////////////////////////////////////////////////////////////////////// /* @@ -22888,10 +23479,15 @@ static void select_describe(JOIN *join, bool need_tmp_table, bool need_order, THD *thd=join->thd; select_result *result=join->result; DBUG_ENTER("select_describe"); +#if 0 join->error= join->print_explain(result, thd->lex->describe, FALSE, /* Not on-the-fly */ need_tmp_table, need_order, distinct, message); +#endif + //psergey-todo: save QPF here, too. + join->save_qpf(thd->lex->query_plan_footprint, need_tmp_table, need_order, + distinct, message); for (SELECT_LEX_UNIT *unit= join->select_lex->first_inner_unit(); unit; diff --git a/sql/sql_select.h b/sql/sql_select.h index 5a3dbccb97f..5ec09fcfcb8 100644 --- a/sql/sql_select.h +++ b/sql/sql_select.h @@ -198,6 +198,12 @@ int rr_sequential(READ_RECORD *info); int rr_sequential_and_unpack(READ_RECORD *info); +#include "opt_qpf.h" + +/************************************************************************************** + * New EXPLAIN structures END + *************************************************************************************/ + class JOIN_CACHE; class SJ_TMP_TABLE; class JOIN_TAB_RANGE; @@ -252,7 +258,9 @@ typedef struct st_join_table { JOIN_TAB_RANGE *bush_children; /* Special content for EXPLAIN 'Extra' column or NULL if none */ - const char *info; + enum Extra_tag info; + //const char *info; + /* Bitmap of TAB_INFO_* bits that encodes special line for EXPLAIN 'Extra' column, or 0 if there is no info. @@ -1454,11 +1462,14 @@ public: { return (unit->item && unit->item->is_in_predicate()); } - +/* int print_explain(select_result_sink *result, uint8 explain_flags, bool on_the_fly, bool need_tmp_table, bool need_order, bool distinct,const char *message); +*/ + int save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, + bool distinct, const char *message); private: /** TRUE if the query contains an aggregate function but has no GROUP -- cgit v1.2.1 From d97ca5f56c400bb675d789d718f52eb1a21d2432 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Mon, 17 Jun 2013 19:39:55 +0400 Subject: [SHOW] EXPLAIN UPDATE/DELETE, code reordering - Add further details, the goal is to pass the testsuite - SJM-nests are not printed correctly yet. --- sql/opt_qpf.cc | 33 ++++++++++++++++++++++++++++++++- sql/opt_qpf.h | 35 +++++++++++++++-------------------- sql/sql_parse.cc | 7 ++++++- sql/sql_select.cc | 46 ++++++++++++++++++++++++++++++++++++++++------ 4 files changed, 93 insertions(+), 28 deletions(-) (limited to 'sql') diff --git a/sql/opt_qpf.cc b/sql/opt_qpf.cc index 12aef844328..90d749ea4b4 100644 --- a/sql/opt_qpf.cc +++ b/sql/opt_qpf.cc @@ -17,6 +17,16 @@ QPF_query::QPF_query() } +QPF_query::~QPF_query() +{ + uint i; + for (i=0 ; i < MAX_TABLES; i++) + delete unions[i]; + for (i=0 ; i < MAX_TABLES; i++) + delete selects[i]; +} + + QPF_node *QPF_query::get_node(uint select_id) { if (unions[select_id]) @@ -178,6 +188,17 @@ int QPF_union::print_explain(QPF_query *query, select_result_sink *output, } +QPF_select::~QPF_select() +{ + if (join_tabs) + { + for (uint i= 0; i< n_join_tabs; i++) + delete join_tabs[i]; + my_free(join_tabs); + } +} + + int QPF_select::print_explain(QPF_query *query, select_result_sink *output, uint8 explain_flags) { @@ -222,6 +243,13 @@ int QPF_select::print_explain(QPF_query *query, select_result_sink *output, } } } + + //psergey-TODO: print children here... + for (int i= 0; i < (int) children.elements(); i++) + { + QPF_node *node= query->get_node(children.at(i)); + node->print_explain(query, output, explain_flags); + } return 0; } @@ -259,7 +287,10 @@ int QPF_table_access::print_explain(select_result_sink *output, uint8 explain_fl /* `possible_keys` column */ //push_str(item_list, "TODO"); - item_list.push_back(item_null); + if (possible_keys_str.length() > 0) + push_string(&item_list, &possible_keys_str); + else + item_list.push_back(item_null); /* `key` */ if (key_set) diff --git a/sql/opt_qpf.h b/sql/opt_qpf.h index 86655f3ed3d..6aa0a5327da 100644 --- a/sql/opt_qpf.h +++ b/sql/opt_qpf.h @@ -48,33 +48,19 @@ class QPF_select : public QPF_node public: enum qpf_node_type get_type() { return QPF_SELECT; } -#if 0 - /* Constructs a finished degenerate join plan */ - QPF_select(int select_id_arg, const char *select_type_arg, const char* msg) : - select_id(select_id_arg), - select_type(select_type_arg), - message(msg), - join_tabs(NULL), n_join_tabs(0) - {} - - /* Constructs an un-finished, non degenerate join plan. */ - QPF_select(int select_id_arg, const char *select_type_arg) : - select_id(select_id_arg), - select_type(select_type_arg), - message(NULL), - join_tabs(NULL), n_join_tabs(0) - {} -#endif QPF_select() : message(NULL), join_tabs(NULL), using_temporary(false), using_filesort(false) {} + + ~QPF_select(); bool add_table(QPF_table_access *tab) { if (!join_tabs) { - join_tabs= (QPF_table_access**) malloc(sizeof(QPF_table_access*) * MAX_TABLES); + join_tabs= (QPF_table_access**) my_malloc(sizeof(QPF_table_access*) * + MAX_TABLES, MYF(0)); n_join_tabs= 0; } join_tabs[n_join_tabs++]= tab; @@ -103,6 +89,13 @@ public: /* Global join attributes. In tabular form, they are printed on the first row */ bool using_temporary; bool using_filesort; + + /* Child selects. TODO: join this with QPF_union's children? */ + Dynamic_array children; + void add_child(int select_no) + { + children.append(select_no); + } void print_tabular(select_result_sink *output, uint8 explain_flags//, //bool *printed_anything @@ -143,10 +136,11 @@ public: This is the whole query. */ -class QPF_query +class QPF_query : public Sql_alloc { public: QPF_query(); + ~QPF_query(); void add_node(QPF_node *node); int print_explain(select_result_sink *output, uint8 explain_flags); @@ -203,7 +197,7 @@ enum Extra_tag }; -class QPF_table_access +class QPF_table_access : public Sql_alloc { public: void push_extra(enum Extra_tag extra_tag); @@ -220,6 +214,7 @@ public: bool used_partitions_set; key_map possible_keys; + StringBuffer<256> possible_keys_str; uint key_no; uint key_length; diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc index aab26e72a65..d6e31f4142c 100644 --- a/sql/sql_parse.cc +++ b/sql/sql_parse.cc @@ -4814,7 +4814,12 @@ static bool execute_sqlcom_select(THD *thd, TABLE_LIST *all_tables) thd->lex->query_plan_footprint= new QPF_query; res= mysql_explain_union(thd, &thd->lex->unit, result); - thd->lex->query_plan_footprint->print_explain(result, thd->lex->describe); + if (!res) + { + thd->lex->query_plan_footprint->print_explain(result, thd->lex->describe); + } + delete thd->lex->query_plan_footprint; + thd->lex->query_plan_footprint= NULL; //psergey-todo: here, produce the EXPLAIN output. // mysql_explain_union() itself is only responsible for calling diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 45090a2cec5..09c28680860 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -22903,6 +22903,21 @@ void QPF_table_access::push_extra(enum Extra_tag extra_tag) extra_tags.append(extra_tag); } +void append_possible_keys(String *str, TABLE *table, key_map possible_keys) +{ + uint j; + for (j=0 ; j < table->s->keys ; j++) + { + if (possible_keys.is_set(j)) + { + if (str->length()) + str->append(','); + str->append(table->key_info[j].name, + strlen(table->key_info[j].name), + system_charset_info); + } + } +} /* Save Query Plan Footprint @@ -22982,9 +22997,6 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, for (JOIN_TAB *tab= first_breadth_first_tab(join, WALK_OPTIMIZATION_TABS); tab; tab= next_breadth_first_tab(join, WALK_OPTIMIZATION_TABS, tab)) { - QPF_table_access *qpt= new QPF_table_access; - qp_sel->add_table(qpt); - if (tab->bush_root_tab) { JOIN_TAB *first_sibling= tab->bush_root_tab->bush_children->start; @@ -23020,7 +23032,6 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, continue; } - if (join->table_access_tabs == join->join_tab && tab == (first_top_tab + join->const_tables) && pre_sort_join_tab) { @@ -23028,8 +23039,12 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, tab= pre_sort_join_tab; } + QPF_table_access *qpt= new QPF_table_access; + qp_sel->add_table(qpt); + /* id */ - qp_sel->select_id= select_id; + // TODO: this can be '2' in case of SJM nests.. + //qp_sel->select_id= select_id; /* select_type */ //const char* stype= printing_materialize_nest? "MATERIALIZED" : @@ -23099,6 +23114,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, /* Build "possible_keys" value */ qpt->possible_keys= tab->keys; + append_possible_keys(&qpt->possible_keys_str, table, tab->keys); /* Build "key", "key_len", and "ref" */ @@ -23379,9 +23395,10 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, */ if (quick_type == QUICK_SELECT_I::QS_TYPE_RANGE) { - qpt->push_extra(ET_USING_MRR); explain_append_mrr_info((QUICK_RANGE_SELECT*)(tab->select->quick), &qpt->mrr_type); + if (qpt->mrr_type.length() > 0) + qpt->push_extra(ET_USING_MRR); } if (need_tmp_table) @@ -23463,6 +23480,23 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, } output->add_node(qp_sel); } + + + /// + for (SELECT_LEX_UNIT *unit= join->select_lex->first_inner_unit(); + unit; + unit= unit->next_unit()) + { + /* + Display subqueries only if they are not parts of eliminated WHERE/ON + clauses. + */ + if (!(unit->item && unit->item->eliminated)) + { + qp_sel->add_child(unit->first_select()->select_number); + } + } + DBUG_RETURN(error); } -- cgit v1.2.1 From 1ec9993155899c4427deb999bff90321da731eb3 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Tue, 18 Jun 2013 08:31:46 +0400 Subject: [SHOW] EXPLAIN UPDATE/DELETE, code re-architecting - Fix more problems to pass the testsuite (not finished yet) --- sql/sql_select.cc | 34 +++++++++++++++++++--------------- 1 file changed, 19 insertions(+), 15 deletions(-) (limited to 'sql') diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 09c28680860..3432e42d32a 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -22929,7 +22929,7 @@ void append_possible_keys(String *str, TABLE *table, key_map possible_keys) int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, bool distinct, const char *message) { - QPF_select *qp_sel; + QPF_select *qp_sel= NULL; const bool on_the_fly= true; JOIN *join= this; /* Legacy: this code used to be a non-member function */ @@ -22944,7 +22944,6 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, DBUG_ASSERT(have_query_plan == QEP_AVAILABLE); /* Don't log this into the slow query log */ - qp_sel= new QPF_select; /* NOTE: the number/types of items pushed into item_list must be in sync with @@ -22952,6 +22951,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, */ if (message) { + qp_sel= new QPF_select; join->select_lex->set_explain_type(on_the_fly); qp_sel->select_id= join->select_lex->select_number; @@ -22981,6 +22981,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, else if (!join->select_lex->master_unit()->derived || join->select_lex->master_unit()->derived->is_materialized_derived()) { + qp_sel= new QPF_select; table_map used_tables=0; if (on_the_fly) @@ -23059,7 +23060,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, int len= my_snprintf(table_name_buffer, sizeof(table_name_buffer)-1, "", table->derived_select_number); - qpt->table_name.set(table_name_buffer, len, cs); + qpt->table_name.append(table_name_buffer, len, cs); } else if (tab->bush_children) { @@ -23074,7 +23075,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, else { TABLE_LIST *real_table= table->pos_in_table_list; - qpt->table_name.set(real_table->alias, strlen(real_table->alias), cs); + qpt->table_name.append(real_table->alias, strlen(real_table->alias), cs); } /* "partitions" column */ @@ -23481,19 +23482,22 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, output->add_node(qp_sel); } - - /// - for (SELECT_LEX_UNIT *unit= join->select_lex->first_inner_unit(); - unit; - unit= unit->next_unit()) + //TODO: can a UNION have subquery children that are not union members? yes, + //perhaps... + if (qp_sel) { - /* - Display subqueries only if they are not parts of eliminated WHERE/ON - clauses. - */ - if (!(unit->item && unit->item->eliminated)) + for (SELECT_LEX_UNIT *unit= join->select_lex->first_inner_unit(); + unit; + unit= unit->next_unit()) { - qp_sel->add_child(unit->first_select()->select_number); + /* + Display subqueries only if they are not parts of eliminated WHERE/ON + clauses. + */ + if (!(unit->item && unit->item->eliminated)) + { + qp_sel->add_child(unit->first_select()->select_number); + } } } -- cgit v1.2.1 From d2ea53aaedad051ceaf59d61f6ae8654bfd5947a Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Tue, 18 Jun 2013 10:57:36 +0400 Subject: [SHOW] EXPLAIN UPDATE/DELETE, code re-architecting - Pass more tests - select with subselects is now shown with type=PRIMARY where it used to be (incorrectly) 'SIMPLE' --- sql/opt_qpf.cc | 39 ++++++++++++++++++++++------ sql/opt_qpf.h | 76 +++++++++++++++++++++++++++++++++++-------------------- sql/sql_select.cc | 62 ++++++++++++++++++++++----------------------- 3 files changed, 111 insertions(+), 66 deletions(-) (limited to 'sql') diff --git a/sql/opt_qpf.cc b/sql/opt_qpf.cc index 90d749ea4b4..8f42809ec85 100644 --- a/sql/opt_qpf.cc +++ b/sql/opt_qpf.cc @@ -99,9 +99,9 @@ int QPF_union::print_explain(QPF_query *query, select_result_sink *output, uint8 explain_flags) { // print all children, in order - for (int i= 0; i < (int) children.elements(); i++) + for (int i= 0; i < (int) union_members.elements(); i++) { - QPF_select *sel= query->get_select(children.at(i)); + QPF_select *sel= query->get_select(union_members.at(i)); sel->print_explain(query, output, explain_flags); } @@ -123,15 +123,15 @@ int QPF_union::print_explain(QPF_query *query, select_result_sink *output, uint len= 6, lastop= 0; memcpy(table_name_buffer, STRING_WITH_LEN("= NAME_LEN) + if (childno < union_members.elements() || len + lastop >= NAME_LEN) { memcpy(table_name_buffer + len, STRING_WITH_LEN("...>") + 1); len+= 4; @@ -184,6 +184,13 @@ int QPF_union::print_explain(QPF_query *query, select_result_sink *output, if (output->send_data(item_list)) return 1; + + for (int i= 0; i < (int) children.elements(); i++) + { + QPF_node *node= query->get_node(children.at(i)); + node->print_explain(query, output, explain_flags); + } + return 0; } @@ -222,7 +229,6 @@ int QPF_select::print_explain(QPF_query *query, select_result_sink *output, if (output->send_data(item_list)) return 1; - return 0; } else { @@ -244,7 +250,6 @@ int QPF_select::print_explain(QPF_query *query, select_result_sink *output, } } - //psergey-TODO: print children here... for (int i= 0; i < (int) children.elements(); i++) { QPF_node *node= query->get_node(children.at(i)); @@ -262,11 +267,17 @@ int QPF_table_access::print_explain(select_result_sink *output, uint8 explain_fl Item *item_null= new Item_null(); //const CHARSET_INFO *cs= system_charset_info; + if (sjm_nest_select_id) + select_id= sjm_nest_select_id; + /* `id` column */ item_list.push_back(new Item_int((int32) select_id)); /* `select_type` column */ - push_str(&item_list, select_type); + if (sjm_nest_select_id) + push_str(&item_list, "MATERIALIZED"); + else + push_str(&item_list, select_type); /* `table` column */ push_string(&item_list, &table_name); @@ -440,6 +451,18 @@ void QPF_table_access::append_tag_name(String *str, enum Extra_tag tag) str->append(join_buffer_type); break; } + case ET_FIRST_MATCH: + { + if (firstmatch_table_name.length()) + { + str->append("FirstMatch("); + str->append(firstmatch_table_name); + str->append(")"); + } + else + str->append(extra_tag_text[tag]); + break; + } default: str->append(extra_tag_text[tag]); } diff --git a/sql/opt_qpf.h b/sql/opt_qpf.h index 6aa0a5327da..9fb2324bef6 100644 --- a/sql/opt_qpf.h +++ b/sql/opt_qpf.h @@ -23,6 +23,14 @@ public: virtual enum qpf_node_type get_type()= 0; virtual int print_explain(QPF_query *query, select_result_sink *output, uint8 explain_flags)=0; + + + Dynamic_array children; + void add_child(int select_no) + { + children.append(select_no); + } + virtual ~QPF_node(){} }; @@ -90,13 +98,6 @@ public: bool using_temporary; bool using_filesort; - /* Child selects. TODO: join this with QPF_union's children? */ - Dynamic_array children; - void add_child(int select_no) - { - children.append(select_no); - } - void print_tabular(select_result_sink *output, uint8 explain_flags//, //bool *printed_anything ); @@ -113,15 +114,26 @@ public: int get_select_id() { - DBUG_ASSERT(children.elements() > 0); - return children.at(0); + DBUG_ASSERT(union_members.elements() > 0); + return union_members.at(0); } - // This has QPF_select children - Dynamic_array children; + /* + Members of the UNION. Note: these are disjoint from UNION's "children". + Example: + + (select * from t1) union + (select * from t2) order by (select col1 from t3 ...) + + here + - select-from-t1 and select-from-t2 are "union members" + - select-from-t3 is the only "child". + + */ + Dynamic_array union_members; void add_select(int select_no) { - children.append(select_no); + union_members.append(select_no); } void push_table_name(List *item_list); int print_explain(QPF_query *query, select_result_sink *output, @@ -204,56 +216,66 @@ public: /* Internals */ public: + /* + 0 means this tab is not inside SJM nest and should use QPF_select's id + other value means the tab is inside an SJM nest. + */ + int sjm_nest_select_id; + /* id and 'select_type' are cared-of by the parent QPF_select */ TABLE *table; - StringBuffer<256> table_name; + StringBuffer<64> table_name; enum join_type type; - StringBuffer<256> used_partitions; + StringBuffer<64> used_partitions; bool used_partitions_set; key_map possible_keys; - StringBuffer<256> possible_keys_str; + StringBuffer<64> possible_keys_str; + /* Not used? */ uint key_no; uint key_length; Dynamic_array extra_tags; //temporary: - StringBuffer<256> key; - StringBuffer<256> key_len; - StringBuffer<256> ref; - bool key_set; - bool key_len_set; - bool ref_set; + bool key_set; /* not set means 'NULL' should be printed */ + StringBuffer<64> key; + + bool key_len_set; /* not set means 'NULL' should be printed */ + StringBuffer<64> key_len; + + bool ref_set; /* not set means 'NULL' should be printed */ + StringBuffer<64> ref; bool rows_set; ha_rows rows; - double filtered; bool filtered_set; + double filtered; /* Various stuff for 'Extra' column*/ uint join_cache_level; // Valid if ET_USING tag is present - StringBuffer<256> quick_info; + StringBuffer<64> quick_info; // Valid if ET_USING_INDEX_FOR_GROUP_BY is present - StringBuffer<256> loose_scan_type; + StringBuffer<64> loose_scan_type; // valid with ET_RANGE_CHECKED_FOR_EACH_RECORD key_map range_checked_map; // valid with ET_USING_MRR - StringBuffer <256> mrr_type; + StringBuffer <64> mrr_type; // valid with ET_USING_JOIN_BUFFER - StringBuffer <256> join_buffer_type; + StringBuffer <64> join_buffer_type; - TABLE *firstmatch_table; + //TABLE *firstmatch_table; + StringBuffer<64> firstmatch_table_name; int print_explain(select_result_sink *output, uint8 explain_flags, uint select_id, const char *select_type, diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 3432e42d32a..91da7526c72 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -22308,7 +22308,7 @@ void explain_append_mrr_info(QUICK_RANGE_SELECT *quick, String *res) sizeof(mrr_str_buf)); if (len > 0) { - res->append(STRING_WITH_LEN("; ")); + //res->append(STRING_WITH_LEN("; ")); res->append(mrr_str_buf, len); } } @@ -22929,7 +22929,7 @@ void append_possible_keys(String *str, TABLE *table, key_map possible_keys) int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, bool distinct, const char *message) { - QPF_select *qp_sel= NULL; + QPF_node *qp_node; const bool on_the_fly= true; JOIN *join= this; /* Legacy: this code used to be a non-member function */ @@ -22951,7 +22951,8 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, */ if (message) { - qp_sel= new QPF_select; + QPF_select *qp_sel; + qp_node= qp_sel= new QPF_select; join->select_lex->set_explain_type(on_the_fly); qp_sel->select_id= join->select_lex->select_number; @@ -22964,6 +22965,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, { select_lex->set_explain_type(on_the_fly); QPF_union *qp_union= new QPF_union; + qp_node= qp_union; SELECT_LEX *child; for (child= select_lex->master_unit()->first_select(); child; @@ -22981,13 +22983,14 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, else if (!join->select_lex->master_unit()->derived || join->select_lex->master_unit()->derived->is_materialized_derived()) { - qp_sel= new QPF_select; + QPF_select *qp_sel; + qp_node= qp_sel= new QPF_select; table_map used_tables=0; if (on_the_fly) join->select_lex->set_explain_type(on_the_fly); - bool printing_materialize_nest= FALSE; + //bool printing_materialize_nest= FALSE; uint select_id= join->select_lex->select_number; qp_sel->select_id= join->select_lex->select_number; @@ -23002,7 +23005,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, { JOIN_TAB *first_sibling= tab->bush_root_tab->bush_children->start; select_id= first_sibling->emb_sj_nest->sj_subq_pred->get_identifier(); - printing_materialize_nest= TRUE; + //printing_materialize_nest= TRUE; } TABLE *table=tab->table; @@ -23042,10 +23045,12 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, QPF_table_access *qpt= new QPF_table_access; qp_sel->add_table(qpt); - + /* id */ - // TODO: this can be '2' in case of SJM nests.. - //qp_sel->select_id= select_id; + if (tab->bush_root_tab) + qpt->sjm_nest_select_id= select_id; + else + qpt->sjm_nest_select_id= 0; /* select_type */ //const char* stype= printing_materialize_nest? "MATERIALIZED" : @@ -23060,7 +23065,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, int len= my_snprintf(table_name_buffer, sizeof(table_name_buffer)-1, "", table->derived_select_number); - qpt->table_name.append(table_name_buffer, len, cs); + qpt->table_name.copy(table_name_buffer, len, cs); } else if (tab->bush_children) { @@ -23070,12 +23075,12 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, sizeof(table_name_buffer)-1, "", ctab->emb_sj_nest->sj_subq_pred->get_identifier()); - qpt->table_name.set(table_name_buffer, len, cs); + qpt->table_name.copy(table_name_buffer, len, cs); } else { TABLE_LIST *real_table= table->pos_in_table_list; - qpt->table_name.append(real_table->alias, strlen(real_table->alias), cs); + qpt->table_name.copy(real_table->alias, strlen(real_table->alias), cs); } /* "partitions" column */ @@ -23433,13 +23438,12 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, else { qpt->push_extra(ET_FIRST_MATCH); - //TABLE *prev_table=tab->do_firstmatch->table; + TABLE *prev_table=tab->do_firstmatch->table; /* TODO: qpt->firstmatch_table... This must be a reference to another QPF element. Or, its index. */ -#if 0 - extra.append(STRING_WITH_LEN("; FirstMatch(")); + // extra.append(STRING_WITH_LEN("; FirstMatch(")); if (prev_table->derived_select_number) { char namebuf[NAME_LEN]; @@ -23447,12 +23451,11 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, int len= my_snprintf(namebuf, sizeof(namebuf)-1, "", prev_table->derived_select_number); - extra.append(namebuf, len); + qpt->firstmatch_table_name.append(namebuf, len); } else - extra.append(prev_table->pos_in_table_list->alias); - extra.append(STRING_WITH_LEN(")")); -#endif + qpt->firstmatch_table_name.append(prev_table->pos_in_table_list->alias); + //extra.append(STRING_WITH_LEN(")")); } } @@ -23484,20 +23487,17 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, //TODO: can a UNION have subquery children that are not union members? yes, //perhaps... - if (qp_sel) + for (SELECT_LEX_UNIT *unit= join->select_lex->first_inner_unit(); + unit; + unit= unit->next_unit()) { - for (SELECT_LEX_UNIT *unit= join->select_lex->first_inner_unit(); - unit; - unit= unit->next_unit()) + /* + Display subqueries only if they are not parts of eliminated WHERE/ON + clauses. + */ + if (!(unit->item && unit->item->eliminated)) { - /* - Display subqueries only if they are not parts of eliminated WHERE/ON - clauses. - */ - if (!(unit->item && unit->item->eliminated)) - { - qp_sel->add_child(unit->first_select()->select_number); - } + qp_node->add_child(unit->first_select()->select_number); } } -- cgit v1.2.1 From 1c6fc3f6b9f7e79331053b5675793d70d0e70af0 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Tue, 18 Jun 2013 19:21:00 +0400 Subject: [SHOW] EXPLAIN UPDATE/DELETE, code re-structuring Part 2 of: - Pass more tests - select with subselects is now shown with type=PRIMARY where it used to be (incorrectly) 'SIMPLE' --- sql/opt_qpf.cc | 3 +++ sql/sql_class.h | 5 +++++ sql/sql_parse.cc | 13 +++++++++++++ sql/sql_update.cc | 11 +++++++++++ 4 files changed, 32 insertions(+) (limited to 'sql') diff --git a/sql/opt_qpf.cc b/sql/opt_qpf.cc index 8f42809ec85..8e8ca06ed24 100644 --- a/sql/opt_qpf.cc +++ b/sql/opt_qpf.cc @@ -182,6 +182,7 @@ int QPF_union::print_explain(QPF_query *query, select_result_sink *output, const CHARSET_INFO *cs= system_charset_info; item_list.push_back(new Item_string(extra_buf.ptr(), extra_buf.length(), cs)); + //output->unit.offset_limit_cnt= 0; if (output->send_data(item_list)) return 1; @@ -209,6 +210,8 @@ QPF_select::~QPF_select() int QPF_select::print_explain(QPF_query *query, select_result_sink *output, uint8 explain_flags) { + //output->unit.offset_limit_cnt= 0; + if (message) { List item_list; diff --git a/sql/sql_class.h b/sql/sql_class.h index bb5b2c4e775..d84f511e5d3 100644 --- a/sql/sql_class.h +++ b/sql/sql_class.h @@ -3401,6 +3401,11 @@ public: void begin_dataset() {} #endif virtual void update_used_tables() {} + + void reset_offset_limit() + { + unit->offset_limit_cnt= 0; + } }; diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc index d6e31f4142c..1513ce61886 100644 --- a/sql/sql_parse.cc +++ b/sql/sql_parse.cc @@ -3273,6 +3273,7 @@ end_with_restore_list: result= NULL; } select_lex->set_explain_type(FALSE); + thd->lex->query_plan_footprint= new QPF_query; } else result= new multi_delete(aux_tables, lex->table_count); @@ -3296,6 +3297,13 @@ end_with_restore_list: { MYSQL_MULTI_DELETE_DONE(res, del_result->num_deleted()); } + else + { + result->reset_offset_limit(); + thd->lex->query_plan_footprint->print_explain(result, thd->lex->describe); + delete thd->lex->query_plan_footprint; + thd->lex->query_plan_footprint= NULL; + } if (res) result->abort_result_set(); /* for both DELETE and EXPLAIN DELETE */ @@ -4816,6 +4824,11 @@ static bool execute_sqlcom_select(THD *thd, TABLE_LIST *all_tables) if (!res) { + /* + Do like the original select_describe did: remove OFFSET from the + top-level LIMIT + */ + result->reset_offset_limit(); thd->lex->query_plan_footprint->print_explain(result, thd->lex->describe); } delete thd->lex->query_plan_footprint; diff --git a/sql/sql_update.cc b/sql/sql_update.cc index 8b1b042e6df..c6bf984c70c 100644 --- a/sql/sql_update.cc +++ b/sql/sql_update.cc @@ -1463,6 +1463,8 @@ bool mysql_multi_update(THD *thd, } select_lex->set_explain_type(FALSE); *result= NULL; /* no multi_update object */ + + thd->lex->query_plan_footprint= new QPF_query; } else { @@ -1492,6 +1494,15 @@ bool mysql_multi_update(THD *thd, DBUG_PRINT("info",("res: %d report_error: %d", res, (int) thd->is_error())); res|= thd->is_error(); + + if (explain) + { + //result->reset_offset_limit(); + thd->lex->query_plan_footprint->print_explain(output, thd->lex->describe); + delete thd->lex->query_plan_footprint; + thd->lex->query_plan_footprint= NULL; + } + if (unlikely(res)) (*result)->abort_result_set(); else -- cgit v1.2.1 From 1951d40a88e3b3fc0d2fac2ba3358d887e738485 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Tue, 18 Jun 2013 21:08:34 +0400 Subject: [SHOW] EXPLAIN UPDATE/DELETE, code re-structuring - Make EXPLAIN UPDATE/DELETE use "Query Plan Footprints", too. --- sql/opt_qpf.cc | 16 ++++-- sql/opt_qpf.h | 7 ++- sql/sql_delete.cc | 152 ++++++++++++++++++++++++++++-------------------------- sql/sql_lex.cc | 6 +-- sql/sql_lex.h | 18 +++++-- sql/sql_update.cc | 68 ++++++++++++++---------- 6 files changed, 152 insertions(+), 115 deletions(-) (limited to 'sql') diff --git a/sql/opt_qpf.cc b/sql/opt_qpf.cc index 8e8ca06ed24..b3d15a74984 100644 --- a/sql/opt_qpf.cc +++ b/sql/opt_qpf.cc @@ -12,6 +12,7 @@ QPF_query::QPF_query() { + upd_del_plan= NULL; memset(&unions, 0, sizeof(unions)); memset(&selects, 0, sizeof(selects)); } @@ -19,6 +20,7 @@ QPF_query::QPF_query() QPF_query::~QPF_query() { + delete upd_del_plan; uint i; for (i=0 ; i < MAX_TABLES; i++) delete unions[i]; @@ -70,9 +72,17 @@ void QPF_query::add_node(QPF_node *node) int QPF_query::print_explain(select_result_sink *output, uint8 explain_flags) { - // Start with id=1 - QPF_node *node= get_node(1); - return node->print_explain(this, output, explain_flags); + if (upd_del_plan) + { + upd_del_plan->print_explain(output, explain_flags); + return 0; + } + else + { + // Start with id=1 + QPF_node *node= get_node(1); + return node->print_explain(this, output, explain_flags); + } } diff --git a/sql/opt_qpf.h b/sql/opt_qpf.h index 9fb2324bef6..82d305261e7 100644 --- a/sql/opt_qpf.h +++ b/sql/opt_qpf.h @@ -161,6 +161,9 @@ public: /* This will return a select (even if there is a union with this id) */ QPF_select *get_select(uint select_id); + + /* Delete_plan inherits from Update_plan */ + Update_plan *upd_del_plan; private: QPF_union *unions[MAX_TABLES]; @@ -269,10 +272,10 @@ public: key_map range_checked_map; // valid with ET_USING_MRR - StringBuffer <64> mrr_type; + StringBuffer<64> mrr_type; // valid with ET_USING_JOIN_BUFFER - StringBuffer <64> join_buffer_type; + StringBuffer<64> join_buffer_type; //TABLE *firstmatch_table; StringBuffer<64> firstmatch_table_name; diff --git a/sql/sql_delete.cc b/sql/sql_delete.cc index 390d9e3945a..f6719d3a91b 100644 --- a/sql/sql_delete.cc +++ b/sql/sql_delete.cc @@ -51,8 +51,7 @@ invoked on a running DELETE statement. */ -int Delete_plan::print_explain(select_result_sink *output, uint8 explain_flags, - bool *printed_anything) +int Delete_plan::print_explain(select_result_sink *output, uint8 explain_flags) { if (deleting_all_rows) { @@ -62,37 +61,15 @@ int Delete_plan::print_explain(select_result_sink *output, uint8 explain_flags, { return 1; } - *printed_anything= true; return 0; } - return Update_plan::print_explain(output, explain_flags, printed_anything); + return Update_plan::print_explain(output, explain_flags); } - -int Update_plan::print_explain(select_result_sink *output, uint8 explain_flags, - bool *printed_anything) +void Update_plan::save_query_plan_footprint() { - if (impossible_where) - { - const char *msg= "Impossible where"; - if (print_explain_message_line(output, explain_flags, 1/*select number*/, - "SIMPLE", msg)) - { - return 1; - } - *printed_anything= true; - return 0; - } + select_lex->set_explain_type(TRUE); - select_lex->set_explain_type(FALSE); - /* - Print an EXPLAIN line. We dont have join, so we can't directly use - JOIN::print_explain. - We do have a SELECT_LEX (TODO but how is it useful? it has select_type.. - and that's it?) - */ - - enum join_type jtype; if (select && select->quick) { int quick_type= select->quick->get_type(); @@ -112,35 +89,53 @@ int Update_plan::print_explain(select_result_sink *output, uint8 explain_flags, jtype= JT_NEXT; } - StringBuffer<128> possible_keys_line; + using_where= test(select && select->cond); + //using_filesort is already set make_possible_keys_line(table, possible_keys, &possible_keys_line); - const char *key_name; - const char *key_len; - - StringBuffer<128> key_str; - StringBuffer<128> key_len_str; - StringBuffer<128> extra_str; - /* Calculate key_len */ if (select && select->quick) { select->quick->add_keys_and_lengths(&key_str, &key_len_str); - key_name= key_str.c_ptr(); - key_len= key_len_str.c_ptr(); } else { - key_name= (index == MAX_KEY)? NULL : table->key_info[index].name; - key_len= NULL; + if (index != MAX_KEY) + { + key_str.append(table->key_info[index].name); + } + // key_len stays NULL } - - if (select && select->cond) - extra_str.append(STRING_WITH_LEN("Using where")); + if (select && select->quick && select->quick->get_type() == QUICK_SELECT_I::QS_TYPE_RANGE) { - explain_append_mrr_info((QUICK_RANGE_SELECT*)select->quick, &extra_str); + explain_append_mrr_info((QUICK_RANGE_SELECT*)select->quick, &mrr_type); + } +} + +int Update_plan::print_explain(select_result_sink *output, uint8 explain_flags) +{ + StringBuffer<64> extra_str; + if (impossible_where) + { + const char *msg= "Impossible where"; + if (print_explain_message_line(output, explain_flags, 1/*select number*/, + "SIMPLE", msg)) + { + return 1; + } + return 0; + } + + if (using_where) + extra_str.append(STRING_WITH_LEN("Using where")); + + if (mrr_type.length() != 0) + { + if (extra_str.length() !=0) + extra_str.append(STRING_WITH_LEN("; ")); + extra_str.append(mrr_type); } if (using_filesort) @@ -160,15 +155,14 @@ int Update_plan::print_explain(select_result_sink *output, uint8 explain_flags, select_lex->type, table->pos_in_table_list->alias, // partitions, - jtype, + (enum join_type) jtype, possible_keys_line.length()? possible_keys_line.c_ptr(): NULL, - key_name, - key_len, + key_str.length()? key_str.c_ptr() : NULL, + key_len_str.length() ? key_len_str.c_ptr() : NULL, NULL, /* 'ref' is always NULL in single-table EXPLAIN DELETE */ select ? select->records : table_rows, extra_str.c_ptr()); - *printed_anything= true; /* psergey-todo: handle all this through saving QPF. @@ -211,10 +205,10 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, SELECT_LEX *select_lex= &thd->lex->select_lex; killed_state killed_status= NOT_KILLED; THD::enum_binlog_query_type query_type= THD::ROW_QUERY_TYPE; - - Delete_plan query_plan; - query_plan.index= MAX_KEY; - query_plan.using_filesort= FALSE; + + Delete_plan *query_plan = new Delete_plan; + query_plan->index= MAX_KEY; + query_plan->using_filesort= FALSE; DBUG_ENTER("mysql_delete"); if (open_and_lock_tables(thd, table_list, TRUE, 0)) @@ -238,8 +232,8 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, } thd_proc_info(thd, "init"); table->map=1; - query_plan.select_lex= &thd->lex->select_lex; - query_plan.table= table; + query_plan->select_lex= &thd->lex->select_lex; + query_plan->table= table; if (mysql_prepare_delete(thd, table_list, &conds)) DBUG_RETURN(TRUE); @@ -314,7 +308,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, ha_rows const maybe_deleted= table->file->stats.records; DBUG_PRINT("debug", ("Trying to use delete_all_rows()")); - query_plan.set_delete_all_rows(maybe_deleted); + query_plan->set_delete_all_rows(maybe_deleted); if (thd->lex->describe) goto exit_without_my_ok; @@ -344,7 +338,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, if (result == Item::COND_FALSE) // Impossible where { limit= 0; - query_plan.set_impossible_where(); + query_plan->set_impossible_where(); if (thd->lex->describe) goto exit_without_my_ok; } @@ -372,7 +366,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, DBUG_RETURN(TRUE); if ((select && select->check_quick(thd, safe_update, limit)) || !limit) { - query_plan.set_impossible_where(); + query_plan->set_impossible_where(); if (thd->lex->describe) goto exit_without_my_ok; @@ -413,20 +407,22 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, if (select && select->quick && select->quick->unique_key_range()) { // Single row select (always "ordered") - query_plan.using_filesort= FALSE; - query_plan.index= MAX_KEY; + query_plan->using_filesort= FALSE; + query_plan->index= MAX_KEY; } else - query_plan.index= get_index_for_order(order, table, select, limit, - &query_plan.using_filesort, - &reverse); + query_plan->index= get_index_for_order(order, table, select, limit, + &query_plan->using_filesort, + &reverse); } - query_plan.select= select; - query_plan.possible_keys= table->quick_keys; - query_plan.table_rows= table->file->stats.records; - thd->lex->upd_del_plan= &query_plan; + query_plan->select= select; + query_plan->possible_keys= table->quick_keys; + query_plan->table_rows= table->file->stats.records; + thd->lex->query_plan_footprint= new QPF_query; + thd->lex->query_plan_footprint->upd_del_plan= query_plan; + /* Ok, we have generated a query plan for the DELETE. - if we're running EXPLAIN DELETE, goto produce explain output @@ -435,11 +431,12 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, if (thd->lex->describe) goto exit_without_my_ok; + query_plan->save_query_plan_footprint(); thd->apc_target.enable(); DBUG_EXECUTE_IF("show_explain_probe_delete_exec_start", dbug_serve_apcs(thd, 1);); - if (query_plan.using_filesort) + if (query_plan->using_filesort) { ha_rows examined_rows; ha_rows found_rows; @@ -447,7 +444,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, SORT_FIELD *sortorder; { - DBUG_ASSERT(query_plan.index == MAX_KEY); + DBUG_ASSERT(query_plan->index == MAX_KEY); table->sort.io_cache= (IO_CACHE *) my_malloc(sizeof(IO_CACHE), MYF(MY_FAE | MY_ZEROFILL | MY_THREAD_SPECIFIC)); @@ -483,7 +480,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, thd->apc_target.disable(); DBUG_RETURN(TRUE); } - if (query_plan.index == MAX_KEY || (select && select->quick)) + if (query_plan->index == MAX_KEY || (select && select->quick)) { if (init_read_record(&info, thd, table, select, 1, 1, FALSE)) { @@ -494,7 +491,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, } } else - init_read_record_idx(&info, thd, table, 1, query_plan.index, reverse); + init_read_record_idx(&info, thd, table, 1, query_plan->index, reverse); init_ftfuncs(thd, select_lex, 1); thd_proc_info(thd, "updating"); @@ -587,6 +584,11 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, (void) table->file->extra(HA_EXTRA_NORMAL); thd->apc_target.disable(); + if (thd->lex->query_plan_footprint) + { + delete thd->lex->query_plan_footprint; + thd->lex->query_plan_footprint= NULL; + } cleanup: /* Invalidate the table in the query cache if something changed. This must @@ -650,21 +652,25 @@ cleanup: /* Special exits */ exit_without_my_ok: - thd->lex->upd_del_plan= &query_plan; - + query_plan->save_query_plan_footprint(); + thd->lex->query_plan_footprint->upd_del_plan= query_plan; + + select_send *result; - bool printed_anything; if (!(result= new select_send())) return 1; /* purecov: inspected */ List dummy; /* note: looked in 5.6 and they too use a dummy list like this */ result->prepare(dummy, &thd->lex->unit); thd->send_explain_fields(result); - int err2= thd->lex->print_explain(result, 0 /* explain flags*/, &printed_anything); + int err2= thd->lex->query_plan_footprint->print_explain(result, 0); if (err2) result->abort_result_set(); else result->send_eof(); + + delete thd->lex->query_plan_footprint; + thd->lex->query_plan_footprint= NULL; delete select; free_underlaid_joins(thd, select_lex); diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc index b2d4ca13823..bc16f61b77e 100644 --- a/sql/sql_lex.cc +++ b/sql/sql_lex.cc @@ -448,7 +448,6 @@ void lex_start(THD *thd) lex->thd= lex->unit.thd= thd; - lex->upd_del_plan= NULL; lex->context_stack.empty(); lex->unit.init_query(); lex->unit.init_select(); @@ -2561,7 +2560,6 @@ LEX::LEX() INITIAL_LEX_PLUGIN_LIST_SIZE, 0); reset_query_tables_list(TRUE); mi.init(); - upd_del_plan= NULL; } @@ -4176,11 +4174,11 @@ bool st_select_lex::is_merged_child_of(st_select_lex *ancestor) int LEX::print_explain(select_result_sink *output, uint8 explain_flags, bool *printed_anything) { - if (upd_del_plan) + /* if (upd_del_plan) { upd_del_plan->print_explain(output, explain_flags, printed_anything); return 0; - } + }*/ //int res= unit.print_explain(output, explain_flags, printed_anything); //psergey-todo: here, we should make Query Plan Footprint, and then produce diff --git a/sql/sql_lex.h b/sql/sql_lex.h index d2a8b59a593..db944ab83ec 100644 --- a/sql/sql_lex.h +++ b/sql/sql_lex.h @@ -2378,6 +2378,7 @@ public: SQL_SELECT *select; uint index; ha_rows table_rows; /* Use if select==NULL */ + /* Top-level select_lex. Most of its fields are not used, we need it only to get to the subqueries. @@ -2390,11 +2391,20 @@ public: /* Set this plan to be a plan to do nothing because of impossible WHRE*/ void set_impossible_where() { impossible_where= true; } - virtual int print_explain(select_result_sink *output, uint8 explain_flags, - bool *printed_anything); + virtual int print_explain(select_result_sink *output, uint8 explain_flags); virtual ~Update_plan() {} Update_plan() : impossible_where(false), using_filesort(false) {} + + void save_query_plan_footprint(); + /* Query Plan Footprint fields */ + // cant use it here: enum join_type + int jtype; + bool using_where; + StringBuffer<128> possible_keys_line; + StringBuffer<128> key_str; + StringBuffer<128> key_len_str; + StringBuffer<64> mrr_type; }; @@ -2414,8 +2424,7 @@ public: deleting_all_rows= true; table_rows= rows_arg; } - int print_explain(select_result_sink *output, uint8 explain_flags, - bool *printed_anything); + int print_explain(select_result_sink *output, uint8 explain_flags); }; @@ -2432,7 +2441,6 @@ struct LEX: public Query_tables_list SELECT_LEX *all_selects_list; /* For single-table DELETE: its query plan */ - Update_plan *upd_del_plan; QPF_query *query_plan_footprint; char *length,*dec,*change; diff --git a/sql/sql_update.cc b/sql/sql_update.cc index c6bf984c70c..a694eb3d360 100644 --- a/sql/sql_update.cc +++ b/sql/sql_update.cc @@ -276,9 +276,7 @@ int mysql_update(THD *thd, ulonglong id; List all_fields; killed_state killed_status= NOT_KILLED; - Update_plan query_plan; - query_plan.index= MAX_KEY; - query_plan.using_filesort= FALSE; + Update_plan *query_plan; bool apc_target_enabled= false; // means was enabled *by code this function* DBUG_ENTER("mysql_update"); @@ -317,9 +315,12 @@ int mysql_update(THD *thd, /* Calculate "table->covering_keys" based on the WHERE */ table->covering_keys= table->s->keys_in_use; table->quick_keys.clear_all(); - - query_plan.select_lex= &thd->lex->select_lex; - query_plan.table= table; + + query_plan= new Update_plan; + query_plan->index= MAX_KEY; + query_plan->using_filesort= FALSE; + query_plan->select_lex= &thd->lex->select_lex; + query_plan->table= table; #ifndef NO_EMBEDDED_ACCESS_CHECKS /* Force privilege re-checking for views after they have been opened. */ want_privilege= (table_list->view ? UPDATE_ACL : @@ -378,7 +379,7 @@ int mysql_update(THD *thd, if (cond_value == Item::COND_FALSE) { limit= 0; // Impossible WHERE - query_plan.set_impossible_where(); + query_plan->set_impossible_where(); if (thd->lex->describe) goto exit_without_my_ok; } @@ -411,7 +412,7 @@ int mysql_update(THD *thd, if (error || !limit || thd->is_error() || (select && select->check_quick(thd, safe_update, limit))) { - query_plan.set_impossible_where(); + query_plan->set_impossible_where(); if (thd->lex->describe) goto exit_without_my_ok; @@ -453,16 +454,16 @@ int mysql_update(THD *thd, if (select && select->quick && select->quick->unique_key_range()) { // Single row select (always "ordered"): Ok to use with key field UPDATE need_sort= FALSE; - query_plan.index= MAX_KEY; + query_plan->index= MAX_KEY; used_key_is_modified= FALSE; } else { - query_plan.index= get_index_for_order(order, table, select, limit, - &need_sort, &reverse); + query_plan->index= get_index_for_order(order, table, select, limit, + &need_sort, &reverse); if (select && select->quick) { - DBUG_ASSERT(need_sort || query_plan.index == select->quick->index); + DBUG_ASSERT(need_sort || query_plan->index == select->quick->index); used_key_is_modified= (!select->quick->unique_key_range() && select->quick->is_keys_used(table->write_set)); } @@ -470,11 +471,11 @@ int mysql_update(THD *thd, { if (need_sort) { // Assign table scan index to check below for modified key fields: - query_plan.index= table->file->key_used_on_scan; + query_plan->index= table->file->key_used_on_scan; } - if (query_plan.index != MAX_KEY) + if (query_plan->index != MAX_KEY) { // Check if we are modifying a key that we are used to search with: - used_key_is_modified= is_key_used(table, query_plan.index, table->write_set); + used_key_is_modified= is_key_used(table, query_plan->index, table->write_set); } } } @@ -484,10 +485,11 @@ int mysql_update(THD *thd, - Save the decisions in the query plan - if we're running EXPLAIN UPDATE, get out */ - query_plan.select= select; - query_plan.possible_keys= table->quick_keys; - query_plan.table_rows= table->file->stats.records; - thd->lex->upd_del_plan= &query_plan; + query_plan->select= select; + query_plan->possible_keys= table->quick_keys; + query_plan->table_rows= table->file->stats.records; + thd->lex->query_plan_footprint= new QPF_query; + thd->lex->query_plan_footprint->upd_del_plan= query_plan; /* Ok, we have generated a query plan for the UPDATE. @@ -496,7 +498,8 @@ int mysql_update(THD *thd, */ if (thd->lex->describe) goto exit_without_my_ok; - + + query_plan->save_query_plan_footprint(); thd->apc_target.enable(); apc_target_enabled= true; DBUG_EXECUTE_IF("show_explain_probe_update_exec_start", @@ -515,8 +518,8 @@ int mysql_update(THD *thd, DBUG_ASSERT(table->read_set == &table->def_read_set); DBUG_ASSERT(table->write_set == &table->def_write_set); - if (query_plan.index < MAX_KEY && old_covering_keys.is_set(query_plan.index)) - table->add_read_columns_used_by_index(query_plan.index); + if (query_plan->index < MAX_KEY && old_covering_keys.is_set(query_plan->index)) + table->add_read_columns_used_by_index(query_plan->index); else table->use_all_columns(); @@ -582,13 +585,13 @@ int mysql_update(THD *thd, Full index scan must be started with init_read_record_idx */ - if (query_plan.index == MAX_KEY || (select && select->quick)) + if (query_plan->index == MAX_KEY || (select && select->quick)) { if (init_read_record(&info, thd, table, select, 0, 1, FALSE)) goto err; } else - init_read_record_idx(&info, thd, table, 1, query_plan.index, reverse); + init_read_record_idx(&info, thd, table, 1, query_plan->index, reverse); thd_proc_info(thd, "Searching rows for update"); ha_rows tmp_limit= limit; @@ -1002,6 +1005,12 @@ err: if (apc_target_enabled) thd->apc_target.disable(); + if (thd->lex->query_plan_footprint) + { + delete thd->lex->query_plan_footprint; + thd->lex->query_plan_footprint= NULL; + } + delete select; free_underlaid_joins(thd, select_lex); table->disable_keyread(); @@ -1010,22 +1019,25 @@ err: exit_without_my_ok: DBUG_ASSERT(!apc_target_enabled); - thd->lex->upd_del_plan= &query_plan; - + query_plan->save_query_plan_footprint(); + thd->lex->query_plan_footprint->upd_del_plan= query_plan; + select_send *result; - bool printed_anything; if (!(result= new select_send())) return 1; /* purecov: inspected */ List dummy; /* note: looked in 5.6 and they too use a dummy list like this */ result->prepare(dummy, &thd->lex->unit); thd->send_explain_fields(result); - int err2= thd->lex->print_explain(result, 0 /* explain flags*/, &printed_anything); + int err2= thd->lex->query_plan_footprint->print_explain(result, 0); if (err2) result->abort_result_set(); else result->send_eof(); + delete thd->lex->query_plan_footprint; + thd->lex->query_plan_footprint= NULL; + delete select; free_underlaid_joins(thd, select_lex); DBUG_RETURN((error >= 0 || thd->is_error()) ? 1 : 0); -- cgit v1.2.1 From 6efa1d8c248e1068829af9b530b6c47747ac3310 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Wed, 19 Jun 2013 18:47:31 +0400 Subject: Fixed comments --- sql/opt_qpf.h | 68 +++++++++++++++++++++++++++++++++++------------------------ 1 file changed, 41 insertions(+), 27 deletions(-) (limited to 'sql') diff --git a/sql/opt_qpf.h b/sql/opt_qpf.h index 82d305261e7..d7e4caa1c97 100644 --- a/sql/opt_qpf.h +++ b/sql/opt_qpf.h @@ -19,37 +19,44 @@ class QPF_node : public Sql_alloc { public: enum qpf_node_type {QPF_UNION, QPF_SELECT}; - virtual enum qpf_node_type get_type()= 0; - virtual int print_explain(QPF_query *query, select_result_sink *output, - uint8 explain_flags)=0; + virtual int get_select_id()= 0; + + /* + A node may have children nodes. When a node's QPF (Query Plan Footprint) is + created, children nodes may not yet have QPFs. This is why we store ids. + */ Dynamic_array children; void add_child(int select_no) { children.append(select_no); } + virtual int print_explain(QPF_query *query, select_result_sink *output, + uint8 explain_flags)=0; + virtual ~QPF_node(){} }; -/* - Nesting. - QPF_select may have children QPF_select-s. - (these can be FROM-subqueries, or subqueries from other clauses) +class QPF_table_access; - As for unions, the standard approach is: - - UNION node can be where the select node can be; - - the union has a select that retrieves results from temptable (a special - kind of child) - - and it has regular children selects that are merged into the union. +/* + Query Plan Footprint of a SELECT. + + A select can be: + - a degenerate case. In this case, message!=NULL, and it contains a + description of what kind of degenerate case it is (e.g. "Impossible + WHERE"). + - a join. Here join_tabs has an array of JOIN_TAB query plan footprints. + + In the non-degenerate case, a SELECT may have a GROUP BY/ORDER BY operation. + In both cases, a select may have children selects (see QPF_node) */ -class QPF_table_access; - class QPF_select : public QPF_node { /*Construction interface */ @@ -76,9 +83,11 @@ public: } public: - int select_id; /* -1 means NULL. */ + int select_id; const char *select_type; + int get_select_id() { return select_id; } + /* If message != NULL, this is a degenerate join plan, and all subsequent members have no info @@ -86,10 +95,8 @@ public: const char *message; /* - According to the discussion: this should be an array of "table - descriptors". - - As for SJ-Materialization. Start_materialize/end_materialize markers? + A flat array of Query Plan Footprints. The order is "just like EXPLAIN + would print them". */ QPF_table_access** join_tabs; uint n_join_tabs; @@ -107,6 +114,12 @@ public: }; +/* + Query Plan Footprint of a UNION. + + A UNION may or may not have "Using filesort". +*/ + class QPF_union : public QPF_node { public: @@ -118,16 +131,15 @@ public: return union_members.at(0); } /* - Members of the UNION. Note: these are disjoint from UNION's "children". + Members of the UNION. Note: these are different from UNION's "children". Example: (select * from t1) union (select * from t2) order by (select col1 from t3 ...) here - - select-from-t1 and select-from-t2 are "union members" + - select-from-t1 and select-from-t2 are "union members", - select-from-t3 is the only "child". - */ Dynamic_array union_members; @@ -145,7 +157,7 @@ public: /* - This is the whole query. + Query Plan Footprint for a query (i.e. a statement) */ class QPF_query : public Sql_alloc @@ -153,8 +165,8 @@ class QPF_query : public Sql_alloc public: QPF_query(); ~QPF_query(); + /* Add a new node */ void add_node(QPF_node *node); - int print_explain(select_result_sink *output, uint8 explain_flags); /* This will return a select, or a union */ QPF_node *get_node(uint select_id); @@ -165,6 +177,8 @@ public: /* Delete_plan inherits from Update_plan */ Update_plan *upd_del_plan; + /* Produce a tabular EXPLAIN output */ + int print_explain(select_result_sink *output, uint8 explain_flags); private: QPF_union *unions[MAX_TABLES]; QPF_select *selects[MAX_TABLES]; @@ -212,6 +226,9 @@ enum Extra_tag }; +/* + Query Plan Footprint for a JOIN_TAB. +*/ class QPF_table_access : public Sql_alloc { public: @@ -287,8 +304,5 @@ private: void append_tag_name(String *str, enum Extra_tag tag); }; -// Update_plan and Delete_plan belong to this kind of structures, too. - // TODO: should Update_plan inherit from QPF_table_access? - -- cgit v1.2.1 From 0a560289aaa8c17e3f1930871088f43efce641e8 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Thu, 20 Jun 2013 15:15:24 +0400 Subject: [SHOW] EXPLAIN UPDATE/DELETE, code re-structuring - Introduce back QueryPlan/QueryPlanFootprint separation for single-table UPDATEs/DELETEs - Create an empty QueryPlanFootprint for all kinds of queries --- sql/opt_qpf.cc | 96 ++++++++++++++++++++++++--- sql/opt_qpf.h | 92 ++++++++++++++++++++++++-- sql/sp_head.cc | 3 + sql/sql_delete.cc | 185 +++++++++++++++++++---------------------------------- sql/sql_lex.cc | 2 + sql/sql_lex.h | 35 +++++----- sql/sql_parse.cc | 24 +++++-- sql/sql_prepare.cc | 4 ++ sql/sql_update.cc | 79 ++++++++--------------- 9 files changed, 309 insertions(+), 211 deletions(-) (limited to 'sql') diff --git a/sql/opt_qpf.cc b/sql/opt_qpf.cc index b3d15a74984..819c0e6cc22 100644 --- a/sql/opt_qpf.cc +++ b/sql/opt_qpf.cc @@ -74,7 +74,7 @@ int QPF_query::print_explain(select_result_sink *output, { if (upd_del_plan) { - upd_del_plan->print_explain(output, explain_flags); + upd_del_plan->print_explain(this, output, explain_flags); return 0; } else @@ -196,12 +196,20 @@ int QPF_union::print_explain(QPF_query *query, select_result_sink *output, if (output->send_data(item_list)) return 1; + return print_explain_for_children(query, output, explain_flags); +} + + +int QPF_node::print_explain_for_children(QPF_query *query, + select_result_sink *output, + uint8 explain_flags) +{ for (int i= 0; i < (int) children.elements(); i++) { QPF_node *node= query->get_node(children.at(i)); - node->print_explain(query, output, explain_flags); + if (node->print_explain(query, output, explain_flags)) + return 1; } - return 0; } @@ -263,12 +271,7 @@ int QPF_select::print_explain(QPF_query *query, select_result_sink *output, } } - for (int i= 0; i < (int) children.elements(); i++) - { - QPF_node *node= query->get_node(children.at(i)); - node->print_explain(query, output, explain_flags); - } - return 0; + return print_explain_for_children(query, output, explain_flags); } @@ -482,3 +485,78 @@ void QPF_table_access::append_tag_name(String *str, enum Extra_tag tag) } +int QPF_delete::print_explain(QPF_query *query, select_result_sink *output, + uint8 explain_flags) +{ + if (deleting_all_rows) + { + const char *msg= "Deleting all rows"; + int res= print_explain_message_line(output, explain_flags, + 1 /*select number*/, + "SIMPLE", msg); + return res; + + } + else + { + return QPF_update::print_explain(query, output, explain_flags); + } +} + + +int QPF_update::print_explain(QPF_query *query, select_result_sink *output, + uint8 explain_flags) +{ + StringBuffer<64> extra_str; + if (impossible_where) + { + const char *msg= "Impossible where"; + int res= print_explain_message_line(output, explain_flags, + 1 /*select number*/, + "SIMPLE", msg); + return res; + } + + if (using_where) + extra_str.append(STRING_WITH_LEN("Using where")); + + if (mrr_type.length() != 0) + { + if (extra_str.length() !=0) + extra_str.append(STRING_WITH_LEN("; ")); + extra_str.append(mrr_type); + } + + if (using_filesort) + { + if (extra_str.length() !=0) + extra_str.append(STRING_WITH_LEN("; ")); + extra_str.append(STRING_WITH_LEN("Using filesort")); + } + + /* + Single-table DELETE commands do not do "Using temporary". + "Using index condition" is also not possible (which is an unjustified limitation) + */ + + print_explain_row(output, explain_flags, + 1, /* id */ + "SIMPLE", + table_name.c_ptr(), + // partitions, + jtype, + possible_keys_line.length()? possible_keys_line.c_ptr(): NULL, + key_str.length()? key_str.c_ptr() : NULL, + key_len_str.length() ? key_len_str.c_ptr() : NULL, + NULL, /* 'ref' is always NULL in single-table EXPLAIN DELETE */ + rows, + extra_str.c_ptr()); + + return print_explain_for_children(query, output, explain_flags); +} + +void delete_qpf_query(QPF_query * query) +{ + delete query; +} + diff --git a/sql/opt_qpf.h b/sql/opt_qpf.h index d7e4caa1c97..6e0bb40c576 100644 --- a/sql/opt_qpf.h +++ b/sql/opt_qpf.h @@ -18,7 +18,7 @@ class QPF_query; class QPF_node : public Sql_alloc { public: - enum qpf_node_type {QPF_UNION, QPF_SELECT}; + enum qpf_node_type {QPF_UNION, QPF_SELECT, QPF_UPDATE, QPF_DELETE }; virtual enum qpf_node_type get_type()= 0; @@ -36,7 +36,9 @@ public: virtual int print_explain(QPF_query *query, select_result_sink *output, uint8 explain_flags)=0; - + + int print_explain_for_children(QPF_query *query, select_result_sink *output, + uint8 explain_flags); virtual ~QPF_node(){} }; @@ -155,9 +157,42 @@ public: bool using_filesort; }; +class QPF_delete; + /* - Query Plan Footprint for a query (i.e. a statement) + Query Plan Footprint (QPF) for a query (i.e. a statement). + + This should be able to survive when the query plan was deleted. Currently, + we do not intend for it survive until after query's MEM_ROOT is freed. It + does surivive freeing of query's items. + + For reference, the process of post-query cleanup is as follows: + + >dispatch_command + | >mysql_parse + | | ... + | | lex_end() + | | ... + | | >THD::cleanup_after_query + | | | ... + | | | free_items() + | | | ... + | | dispatch_command + + That is, the order of actions is: + - free query's Items + - write to slow query log + - free query's MEM_ROOT + */ class QPF_query : public Sql_alloc @@ -174,8 +209,8 @@ public: /* This will return a select (even if there is a union with this id) */ QPF_select *get_select(uint select_id); - /* Delete_plan inherits from Update_plan */ - Update_plan *upd_del_plan; + /* QPF_delete inherits from QPF_update */ + QPF_update *upd_del_plan; /* Produce a tabular EXPLAIN output */ int print_explain(select_result_sink *output, uint8 explain_flags); @@ -304,5 +339,50 @@ private: void append_tag_name(String *str, enum Extra_tag tag); }; -// TODO: should Update_plan inherit from QPF_table_access? + +/* + Query Plan Footprint for an UPDATE statement +*/ + +class QPF_update : public QPF_node +{ +public: + virtual enum qpf_node_type get_type() { return QPF_UPDATE; } + virtual int get_select_id() { return 1; /* always root */ } + + bool impossible_where; + StringBuffer<64> table_name; + + enum join_type jtype; + StringBuffer<128> possible_keys_line; + StringBuffer<128> key_str; + StringBuffer<128> key_len_str; + StringBuffer<64> mrr_type; + + bool using_where; + ha_rows rows; + + bool using_filesort; + + virtual int print_explain(QPF_query *query, select_result_sink *output, + uint8 explain_flags); +}; + + +/* + Query Plan Footprint for a DELETE statement +*/ + +class QPF_delete: public QPF_update +{ +public: + bool deleting_all_rows; + + virtual enum qpf_node_type get_type() { return QPF_DELETE; } + virtual int get_select_id() { return 1; /* always root */ } + + virtual int print_explain(QPF_query *query, select_result_sink *output, + uint8 explain_flags); +}; + diff --git a/sql/sp_head.cc b/sql/sp_head.cc index f0a87673857..3cc3a3893bb 100644 --- a/sql/sp_head.cc +++ b/sql/sp_head.cc @@ -3006,6 +3006,9 @@ sp_lex_keeper::reset_lex_and_exec_core(THD *thd, uint *nextp, else if (! thd->in_sub_stmt) thd->mdl_context.release_statement_locks(); } + + delete_qpf_query(m_lex->query_plan_footprint); + m_lex->query_plan_footprint= NULL; if (m_lex->query_tables_own_last) { diff --git a/sql/sql_delete.cc b/sql/sql_delete.cc index f6719d3a91b..602831829d7 100644 --- a/sql/sql_delete.cc +++ b/sql/sql_delete.cc @@ -51,25 +51,44 @@ invoked on a running DELETE statement. */ -int Delete_plan::print_explain(select_result_sink *output, uint8 explain_flags) +void Delete_plan::save_query_plan_footprint(QPF_query *query) { + QPF_delete* qpf= new QPF_delete; + if (deleting_all_rows) { - const char *msg= "Deleting all rows"; - if (print_explain_message_line(output, explain_flags, 1/*select number*/, - "SIMPLE", msg)) - { - return 1; - } - return 0; + qpf->deleting_all_rows= true; } - return Update_plan::print_explain(output, explain_flags); + else + { + Update_plan::save_query_plan_footprint_intern(qpf); + } + + query->upd_del_plan= qpf; } -void Update_plan::save_query_plan_footprint() + +void Update_plan::save_query_plan_footprint(QPF_query *query) { - select_lex->set_explain_type(TRUE); + QPF_update* qpf= new QPF_update; + save_query_plan_footprint_intern(qpf); + query->upd_del_plan= qpf; +} + +void Update_plan::save_query_plan_footprint_intern(QPF_update *qpf) +{ + qpf->table_name.append(table->pos_in_table_list->alias); + if (impossible_where) + { + qpf->impossible_where= true; + return; + } + + // TODO: do we need the following: select_type + //select_lex->set_explain_type(TRUE); + + /* Set jtype */ if (select && select->quick) { int quick_type= select->quick->get_type(); @@ -77,106 +96,46 @@ void Update_plan::save_query_plan_footprint() (quick_type == QUICK_SELECT_I::QS_TYPE_INDEX_INTERSECT) || (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_INTERSECT) || (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_UNION)) - jtype= JT_INDEX_MERGE; + qpf->jtype= JT_INDEX_MERGE; else - jtype= JT_RANGE; + qpf->jtype= JT_RANGE; } else { if (index == MAX_KEY) - jtype= JT_ALL; + qpf->jtype= JT_ALL; else - jtype= JT_NEXT; + qpf->jtype= JT_NEXT; } - using_where= test(select && select->cond); + qpf->using_where= test(select && select->cond); + qpf->using_filesort= using_filesort; + //using_filesort is already set - make_possible_keys_line(table, possible_keys, &possible_keys_line); + make_possible_keys_line(table, possible_keys, &qpf->possible_keys_line); /* Calculate key_len */ if (select && select->quick) { - select->quick->add_keys_and_lengths(&key_str, &key_len_str); + select->quick->add_keys_and_lengths(&qpf->key_str, &qpf->key_len_str); } else { if (index != MAX_KEY) { - key_str.append(table->key_info[index].name); + qpf->key_str.append(table->key_info[index].name); } // key_len stays NULL } + qpf->rows= select ? select->records : table_rows; if (select && select->quick && select->quick->get_type() == QUICK_SELECT_I::QS_TYPE_RANGE) { - explain_append_mrr_info((QUICK_RANGE_SELECT*)select->quick, &mrr_type); + explain_append_mrr_info((QUICK_RANGE_SELECT*)select->quick, &qpf->mrr_type); } } -int Update_plan::print_explain(select_result_sink *output, uint8 explain_flags) -{ - StringBuffer<64> extra_str; - if (impossible_where) - { - const char *msg= "Impossible where"; - if (print_explain_message_line(output, explain_flags, 1/*select number*/, - "SIMPLE", msg)) - { - return 1; - } - return 0; - } - - if (using_where) - extra_str.append(STRING_WITH_LEN("Using where")); - - if (mrr_type.length() != 0) - { - if (extra_str.length() !=0) - extra_str.append(STRING_WITH_LEN("; ")); - extra_str.append(mrr_type); - } - - if (using_filesort) - { - if (extra_str.length() !=0) - extra_str.append(STRING_WITH_LEN("; ")); - extra_str.append(STRING_WITH_LEN("Using filesort")); - } - - /* - Single-table DELETE commands do not do "Using temporary". - "Using index condition" is also not possible (which is an unjustified limitation) - */ - - print_explain_row(output, explain_flags, - 1, /* id */ - select_lex->type, - table->pos_in_table_list->alias, - // partitions, - (enum join_type) jtype, - possible_keys_line.length()? possible_keys_line.c_ptr(): NULL, - key_str.length()? key_str.c_ptr() : NULL, - key_len_str.length() ? key_len_str.c_ptr() : NULL, - NULL, /* 'ref' is always NULL in single-table EXPLAIN DELETE */ - select ? select->records : table_rows, - extra_str.c_ptr()); - - /* - psergey-todo: handle all this through saving QPF. - - for (SELECT_LEX_UNIT *unit= select_lex->first_inner_unit(); - unit; - unit= unit->next_unit()) - { - if (unit->print_explain(output, explain_flags, printed_anything)) - return 1; - } - */ - return 0; -} - /** Implement DELETE SQL word. @@ -205,10 +164,10 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, SELECT_LEX *select_lex= &thd->lex->select_lex; killed_state killed_status= NOT_KILLED; THD::enum_binlog_query_type query_type= THD::ROW_QUERY_TYPE; - - Delete_plan *query_plan = new Delete_plan; - query_plan->index= MAX_KEY; - query_plan->using_filesort= FALSE; + + Delete_plan query_plan; + query_plan.index= MAX_KEY; + query_plan.using_filesort= FALSE; DBUG_ENTER("mysql_delete"); if (open_and_lock_tables(thd, table_list, TRUE, 0)) @@ -232,8 +191,8 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, } thd_proc_info(thd, "init"); table->map=1; - query_plan->select_lex= &thd->lex->select_lex; - query_plan->table= table; + query_plan.select_lex= &thd->lex->select_lex; + query_plan.table= table; if (mysql_prepare_delete(thd, table_list, &conds)) DBUG_RETURN(TRUE); @@ -308,7 +267,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, ha_rows const maybe_deleted= table->file->stats.records; DBUG_PRINT("debug", ("Trying to use delete_all_rows()")); - query_plan->set_delete_all_rows(maybe_deleted); + query_plan.set_delete_all_rows(maybe_deleted); if (thd->lex->describe) goto exit_without_my_ok; @@ -338,7 +297,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, if (result == Item::COND_FALSE) // Impossible where { limit= 0; - query_plan->set_impossible_where(); + query_plan.set_impossible_where(); if (thd->lex->describe) goto exit_without_my_ok; } @@ -366,7 +325,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, DBUG_RETURN(TRUE); if ((select && select->check_quick(thd, safe_update, limit)) || !limit) { - query_plan->set_impossible_where(); + query_plan.set_impossible_where(); if (thd->lex->describe) goto exit_without_my_ok; @@ -407,22 +366,19 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, if (select && select->quick && select->quick->unique_key_range()) { // Single row select (always "ordered") - query_plan->using_filesort= FALSE; - query_plan->index= MAX_KEY; + query_plan.using_filesort= FALSE; + query_plan.index= MAX_KEY; } else - query_plan->index= get_index_for_order(order, table, select, limit, - &query_plan->using_filesort, - &reverse); + query_plan.index= get_index_for_order(order, table, select, limit, + &query_plan.using_filesort, + &reverse); } - query_plan->select= select; - query_plan->possible_keys= table->quick_keys; - query_plan->table_rows= table->file->stats.records; + query_plan.select= select; + query_plan.possible_keys= table->quick_keys; + query_plan.table_rows= table->file->stats.records; - thd->lex->query_plan_footprint= new QPF_query; - thd->lex->query_plan_footprint->upd_del_plan= query_plan; - /* Ok, we have generated a query plan for the DELETE. - if we're running EXPLAIN DELETE, goto produce explain output @@ -431,12 +387,13 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, if (thd->lex->describe) goto exit_without_my_ok; - query_plan->save_query_plan_footprint(); + query_plan.save_query_plan_footprint(thd->lex->query_plan_footprint); thd->apc_target.enable(); + DBUG_EXECUTE_IF("show_explain_probe_delete_exec_start", dbug_serve_apcs(thd, 1);); - if (query_plan->using_filesort) + if (query_plan.using_filesort) { ha_rows examined_rows; ha_rows found_rows; @@ -444,7 +401,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, SORT_FIELD *sortorder; { - DBUG_ASSERT(query_plan->index == MAX_KEY); + DBUG_ASSERT(query_plan.index == MAX_KEY); table->sort.io_cache= (IO_CACHE *) my_malloc(sizeof(IO_CACHE), MYF(MY_FAE | MY_ZEROFILL | MY_THREAD_SPECIFIC)); @@ -480,7 +437,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, thd->apc_target.disable(); DBUG_RETURN(TRUE); } - if (query_plan->index == MAX_KEY || (select && select->quick)) + if (query_plan.index == MAX_KEY || (select && select->quick)) { if (init_read_record(&info, thd, table, select, 1, 1, FALSE)) { @@ -491,7 +448,7 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, } } else - init_read_record_idx(&info, thd, table, 1, query_plan->index, reverse); + init_read_record_idx(&info, thd, table, 1, query_plan.index, reverse); init_ftfuncs(thd, select_lex, 1); thd_proc_info(thd, "updating"); @@ -584,11 +541,6 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, (void) table->file->extra(HA_EXTRA_NORMAL); thd->apc_target.disable(); - if (thd->lex->query_plan_footprint) - { - delete thd->lex->query_plan_footprint; - thd->lex->query_plan_footprint= NULL; - } cleanup: /* Invalidate the table in the query cache if something changed. This must @@ -652,9 +604,7 @@ cleanup: /* Special exits */ exit_without_my_ok: - query_plan->save_query_plan_footprint(); - thd->lex->query_plan_footprint->upd_del_plan= query_plan; - + query_plan.save_query_plan_footprint(thd->lex->query_plan_footprint); select_send *result; if (!(result= new select_send())) @@ -669,9 +619,6 @@ exit_without_my_ok: else result->send_eof(); - delete thd->lex->query_plan_footprint; - thd->lex->query_plan_footprint= NULL; - delete select; free_underlaid_joins(thd, select_lex); //table->set_keyread(false); diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc index bc16f61b77e..6ad7b288a4b 100644 --- a/sql/sql_lex.cc +++ b/sql/sql_lex.cc @@ -447,6 +447,8 @@ void lex_start(THD *thd) DBUG_ENTER("lex_start"); lex->thd= lex->unit.thd= thd; + + lex->query_plan_footprint= NULL; lex->context_stack.empty(); lex->unit.init_query(); diff --git a/sql/sql_lex.h b/sql/sql_lex.h index db944ab83ec..47d01f2e137 100644 --- a/sql/sql_lex.h +++ b/sql/sql_lex.h @@ -619,6 +619,8 @@ class select_union; class Procedure; class QPF_query; +void delete_qpf_query(QPF_query * query); + class st_select_lex_unit: public st_select_lex_node { protected: TABLE_LIST result_table_list; @@ -2360,15 +2362,18 @@ protected: LEX *m_lex; }; + class Delete_plan; class SQL_SELECT; +class QPF_query; +class QPF_update; + /* Query plan of a single-table UPDATE. (This is actually a plan for single-table DELETE also) - - TODO: this should be a query plan footprint, not a query plan. */ + class Update_plan { protected: @@ -2378,10 +2383,9 @@ public: SQL_SELECT *select; uint index; ha_rows table_rows; /* Use if select==NULL */ - - /* + /* Top-level select_lex. Most of its fields are not used, we need it only to - get to the subqueries. + get to the subqueries. */ SELECT_LEX *select_lex; @@ -2391,20 +2395,11 @@ public: /* Set this plan to be a plan to do nothing because of impossible WHRE*/ void set_impossible_where() { impossible_where= true; } - virtual int print_explain(select_result_sink *output, uint8 explain_flags); + void save_query_plan_footprint(QPF_query *query); + void save_query_plan_footprint_intern(QPF_update *qpf); virtual ~Update_plan() {} Update_plan() : impossible_where(false), using_filesort(false) {} - - void save_query_plan_footprint(); - /* Query Plan Footprint fields */ - // cant use it here: enum join_type - int jtype; - bool using_where; - StringBuffer<128> possible_keys_line; - StringBuffer<128> key_str; - StringBuffer<128> key_len_str; - StringBuffer<64> mrr_type; }; @@ -2424,11 +2419,11 @@ public: deleting_all_rows= true; table_rows= rows_arg; } - int print_explain(select_result_sink *output, uint8 explain_flags); + + void save_query_plan_footprint(QPF_query *query); }; -class QPF_query; /* The state of the lex parsing. This is saved in the THD struct */ struct LEX: public Query_tables_list @@ -2439,8 +2434,8 @@ struct LEX: public Query_tables_list SELECT_LEX *current_select; /* list of all SELECT_LEX */ SELECT_LEX *all_selects_list; - - /* For single-table DELETE: its query plan */ + + /* Query Plan Footprint of a currently running select */ QPF_query *query_plan_footprint; char *length,*dec,*change; diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc index 1513ce61886..474d3889b53 100644 --- a/sql/sql_parse.cc +++ b/sql/sql_parse.cc @@ -598,6 +598,10 @@ static void handle_bootstrap_impl(THD *thd) #if defined(ENABLED_PROFILING) thd->profiling.finish_current_query(); #endif + // + delete thd->lex->query_plan_footprint; + thd->lex->query_plan_footprint= NULL; + // if (bootstrap_error) break; @@ -1484,6 +1488,7 @@ bool dispatch_command(enum enum_server_command command, THD *thd, thd->update_all_stats(); log_slow_statement(thd); + /* psergey-todo: this is the place we could print EXPLAIN to slow query log */ thd_proc_info(thd, "cleaning up"); thd->reset_query(); @@ -1518,6 +1523,9 @@ void log_slow_statement(THD *thd) { DBUG_ENTER("log_slow_statement"); + delete thd->lex->query_plan_footprint; + thd->lex->query_plan_footprint= NULL; + /* The following should never be true with our current code base, but better to keep this here so we don't accidently try to log a @@ -1526,6 +1534,7 @@ void log_slow_statement(THD *thd) if (unlikely(thd->in_sub_stmt)) DBUG_VOID_RETURN; // Don't set time for sub stmt + /* Follow the slow log filter configuration. */ if (!thd->enable_slow_log || !(thd->variables.log_slow_filter & thd->query_plan_flags)) @@ -2178,6 +2187,9 @@ mysql_execute_command(THD *thd) /* Release metadata locks acquired in this transaction. */ thd->mdl_context.release_transactional_locks(); } + + DBUG_ASSERT(!thd->lex->query_plan_footprint); + thd->lex->query_plan_footprint= new QPF_query; #ifndef DBUG_OFF if (lex->sql_command != SQLCOM_SET_OPTION) @@ -3273,7 +3285,7 @@ end_with_restore_list: result= NULL; } select_lex->set_explain_type(FALSE); - thd->lex->query_plan_footprint= new QPF_query; + //thd->lex->query_plan_footprint= new QPF_query; } else result= new multi_delete(aux_tables, lex->table_count); @@ -3301,8 +3313,8 @@ end_with_restore_list: { result->reset_offset_limit(); thd->lex->query_plan_footprint->print_explain(result, thd->lex->describe); - delete thd->lex->query_plan_footprint; - thd->lex->query_plan_footprint= NULL; + //delete thd->lex->query_plan_footprint; + //thd->lex->query_plan_footprint= NULL; } if (res) @@ -4819,7 +4831,7 @@ static bool execute_sqlcom_select(THD *thd, TABLE_LIST *all_tables) if (!(result= new select_send())) return 1; /* purecov: inspected */ thd->send_explain_fields(result); - thd->lex->query_plan_footprint= new QPF_query; + //thd->lex->query_plan_footprint= new QPF_query; res= mysql_explain_union(thd, &thd->lex->unit, result); if (!res) @@ -4831,8 +4843,8 @@ static bool execute_sqlcom_select(THD *thd, TABLE_LIST *all_tables) result->reset_offset_limit(); thd->lex->query_plan_footprint->print_explain(result, thd->lex->describe); } - delete thd->lex->query_plan_footprint; - thd->lex->query_plan_footprint= NULL; + //delete thd->lex->query_plan_footprint; + //thd->lex->query_plan_footprint= NULL; //psergey-todo: here, produce the EXPLAIN output. // mysql_explain_union() itself is only responsible for calling diff --git a/sql/sql_prepare.cc b/sql/sql_prepare.cc index 71b4a0cf817..d81070b7406 100644 --- a/sql/sql_prepare.cc +++ b/sql/sql_prepare.cc @@ -2486,6 +2486,7 @@ void reinit_stmt_before_use(THD *thd, LEX *lex) object and because of this can be used in different threads. */ lex->thd= thd; + DBUG_ASSERT(!lex->query_plan_footprint); if (lex->empty_field_list_on_rset) { @@ -3925,6 +3926,9 @@ bool Prepared_statement::execute(String *expanded_query, bool open_cursor) if (! cursor) cleanup_stmt(); + //psergey: TODO the "EXECUTE problem" is here + delete_qpf_query(thd->lex->query_plan_footprint); + thd->lex->query_plan_footprint= NULL; thd->set_statement(&stmt_backup); thd->stmt_arena= old_stmt_arena; diff --git a/sql/sql_update.cc b/sql/sql_update.cc index a694eb3d360..ce56a725567 100644 --- a/sql/sql_update.cc +++ b/sql/sql_update.cc @@ -276,7 +276,9 @@ int mysql_update(THD *thd, ulonglong id; List all_fields; killed_state killed_status= NOT_KILLED; - Update_plan *query_plan; + Update_plan query_plan; + query_plan.index= MAX_KEY; + query_plan.using_filesort= FALSE; bool apc_target_enabled= false; // means was enabled *by code this function* DBUG_ENTER("mysql_update"); @@ -315,12 +317,9 @@ int mysql_update(THD *thd, /* Calculate "table->covering_keys" based on the WHERE */ table->covering_keys= table->s->keys_in_use; table->quick_keys.clear_all(); - - query_plan= new Update_plan; - query_plan->index= MAX_KEY; - query_plan->using_filesort= FALSE; - query_plan->select_lex= &thd->lex->select_lex; - query_plan->table= table; + + query_plan.select_lex= &thd->lex->select_lex; + query_plan.table= table; #ifndef NO_EMBEDDED_ACCESS_CHECKS /* Force privilege re-checking for views after they have been opened. */ want_privilege= (table_list->view ? UPDATE_ACL : @@ -379,7 +378,7 @@ int mysql_update(THD *thd, if (cond_value == Item::COND_FALSE) { limit= 0; // Impossible WHERE - query_plan->set_impossible_where(); + query_plan.set_impossible_where(); if (thd->lex->describe) goto exit_without_my_ok; } @@ -412,7 +411,7 @@ int mysql_update(THD *thd, if (error || !limit || thd->is_error() || (select && select->check_quick(thd, safe_update, limit))) { - query_plan->set_impossible_where(); + query_plan.set_impossible_where(); if (thd->lex->describe) goto exit_without_my_ok; @@ -454,16 +453,16 @@ int mysql_update(THD *thd, if (select && select->quick && select->quick->unique_key_range()) { // Single row select (always "ordered"): Ok to use with key field UPDATE need_sort= FALSE; - query_plan->index= MAX_KEY; + query_plan.index= MAX_KEY; used_key_is_modified= FALSE; } else { - query_plan->index= get_index_for_order(order, table, select, limit, - &need_sort, &reverse); + query_plan.index= get_index_for_order(order, table, select, limit, + &need_sort, &reverse); if (select && select->quick) { - DBUG_ASSERT(need_sort || query_plan->index == select->quick->index); + DBUG_ASSERT(need_sort || query_plan.index == select->quick->index); used_key_is_modified= (!select->quick->unique_key_range() && select->quick->is_keys_used(table->write_set)); } @@ -471,11 +470,11 @@ int mysql_update(THD *thd, { if (need_sort) { // Assign table scan index to check below for modified key fields: - query_plan->index= table->file->key_used_on_scan; + query_plan.index= table->file->key_used_on_scan; } - if (query_plan->index != MAX_KEY) + if (query_plan.index != MAX_KEY) { // Check if we are modifying a key that we are used to search with: - used_key_is_modified= is_key_used(table, query_plan->index, table->write_set); + used_key_is_modified= is_key_used(table, query_plan.index, table->write_set); } } } @@ -485,11 +484,9 @@ int mysql_update(THD *thd, - Save the decisions in the query plan - if we're running EXPLAIN UPDATE, get out */ - query_plan->select= select; - query_plan->possible_keys= table->quick_keys; - query_plan->table_rows= table->file->stats.records; - thd->lex->query_plan_footprint= new QPF_query; - thd->lex->query_plan_footprint->upd_del_plan= query_plan; + query_plan.select= select; + query_plan.possible_keys= table->quick_keys; + query_plan.table_rows= table->file->stats.records; /* Ok, we have generated a query plan for the UPDATE. @@ -498,8 +495,8 @@ int mysql_update(THD *thd, */ if (thd->lex->describe) goto exit_without_my_ok; - - query_plan->save_query_plan_footprint(); + + query_plan.save_query_plan_footprint(thd->lex->query_plan_footprint); thd->apc_target.enable(); apc_target_enabled= true; DBUG_EXECUTE_IF("show_explain_probe_update_exec_start", @@ -518,8 +515,8 @@ int mysql_update(THD *thd, DBUG_ASSERT(table->read_set == &table->def_read_set); DBUG_ASSERT(table->write_set == &table->def_write_set); - if (query_plan->index < MAX_KEY && old_covering_keys.is_set(query_plan->index)) - table->add_read_columns_used_by_index(query_plan->index); + if (query_plan.index < MAX_KEY && old_covering_keys.is_set(query_plan.index)) + table->add_read_columns_used_by_index(query_plan.index); else table->use_all_columns(); @@ -585,13 +582,13 @@ int mysql_update(THD *thd, Full index scan must be started with init_read_record_idx */ - if (query_plan->index == MAX_KEY || (select && select->quick)) + if (query_plan.index == MAX_KEY || (select && select->quick)) { if (init_read_record(&info, thd, table, select, 0, 1, FALSE)) goto err; } else - init_read_record_idx(&info, thd, table, 1, query_plan->index, reverse); + init_read_record_idx(&info, thd, table, 1, query_plan.index, reverse); thd_proc_info(thd, "Searching rows for update"); ha_rows tmp_limit= limit; @@ -1005,12 +1002,6 @@ err: if (apc_target_enabled) thd->apc_target.disable(); - if (thd->lex->query_plan_footprint) - { - delete thd->lex->query_plan_footprint; - thd->lex->query_plan_footprint= NULL; - } - delete select; free_underlaid_joins(thd, select_lex); table->disable_keyread(); @@ -1019,25 +1010,22 @@ err: exit_without_my_ok: DBUG_ASSERT(!apc_target_enabled); - query_plan->save_query_plan_footprint(); - thd->lex->query_plan_footprint->upd_del_plan= query_plan; - + query_plan.save_query_plan_footprint(thd->lex->query_plan_footprint); + select_send *result; + bool printed_anything; if (!(result= new select_send())) return 1; /* purecov: inspected */ List dummy; /* note: looked in 5.6 and they too use a dummy list like this */ result->prepare(dummy, &thd->lex->unit); thd->send_explain_fields(result); - int err2= thd->lex->query_plan_footprint->print_explain(result, 0); + int err2= thd->lex->print_explain(result, 0 /* explain flags*/, &printed_anything); if (err2) result->abort_result_set(); else result->send_eof(); - delete thd->lex->query_plan_footprint; - thd->lex->query_plan_footprint= NULL; - delete select; free_underlaid_joins(thd, select_lex); DBUG_RETURN((error >= 0 || thd->is_error()) ? 1 : 0); @@ -1475,8 +1463,6 @@ bool mysql_multi_update(THD *thd, } select_lex->set_explain_type(FALSE); *result= NULL; /* no multi_update object */ - - thd->lex->query_plan_footprint= new QPF_query; } else { @@ -1506,15 +1492,6 @@ bool mysql_multi_update(THD *thd, DBUG_PRINT("info",("res: %d report_error: %d", res, (int) thd->is_error())); res|= thd->is_error(); - - if (explain) - { - //result->reset_offset_limit(); - thd->lex->query_plan_footprint->print_explain(output, thd->lex->describe); - delete thd->lex->query_plan_footprint; - thd->lex->query_plan_footprint= NULL; - } - if (unlikely(res)) (*result)->abort_result_set(); else -- cgit v1.2.1 From 52cfa54c1d211a17a9df7c38a4568ddc4d09e6d9 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Thu, 20 Jun 2013 20:58:26 +0400 Subject: [SHOW] EXPLAIN UPDATE/DELETE, code re-structuring Single table UPDATE/DELETE - Correctly print type=SIMPLE vs type=PRIMARY - Handle UPDATE/DELETE of mergeable VIEWs: we get the VIEW's select as the first subquery. (MySQL 5.6 doesn't print it because it finds that the subquery is not attached to any select) --- sql/opt_qpf.cc | 10 +++++++--- sql/opt_qpf.h | 2 ++ sql/sql_delete.cc | 42 ++++++++++++++++++++++++++++++++++++------ sql/sql_lex.cc | 7 +++++++ sql/sql_lex.h | 8 +++----- sql/sql_update.cc | 10 ++++++++-- 6 files changed, 63 insertions(+), 16 deletions(-) (limited to 'sql') diff --git a/sql/opt_qpf.cc b/sql/opt_qpf.cc index 819c0e6cc22..425823df9e1 100644 --- a/sql/opt_qpf.cc +++ b/sql/opt_qpf.cc @@ -49,6 +49,7 @@ void QPF_query::add_node(QPF_node *node) if (node->get_type() == QPF_node::QPF_UNION) { QPF_union *u= (QPF_union*)node; + DBUG_ASSERT(!unions[u->get_select_id()]); unions[u->get_select_id()]= u; } else @@ -60,7 +61,10 @@ void QPF_query::add_node(QPF_node *node) DBUG_ASSERT(0); } else + { + DBUG_ASSERT(!selects[sel->select_id]); selects[sel->select_id] = sel; + } } } @@ -493,7 +497,7 @@ int QPF_delete::print_explain(QPF_query *query, select_result_sink *output, const char *msg= "Deleting all rows"; int res= print_explain_message_line(output, explain_flags, 1 /*select number*/, - "SIMPLE", msg); + select_type, msg); return res; } @@ -513,7 +517,7 @@ int QPF_update::print_explain(QPF_query *query, select_result_sink *output, const char *msg= "Impossible where"; int res= print_explain_message_line(output, explain_flags, 1 /*select number*/, - "SIMPLE", msg); + select_type, msg); return res; } @@ -541,7 +545,7 @@ int QPF_update::print_explain(QPF_query *query, select_result_sink *output, print_explain_row(output, explain_flags, 1, /* id */ - "SIMPLE", + select_type, table_name.c_ptr(), // partitions, jtype, diff --git a/sql/opt_qpf.h b/sql/opt_qpf.h index 6e0bb40c576..53839ecbac8 100644 --- a/sql/opt_qpf.h +++ b/sql/opt_qpf.h @@ -350,6 +350,8 @@ public: virtual enum qpf_node_type get_type() { return QPF_UPDATE; } virtual int get_select_id() { return 1; /* always root */ } + const char *select_type; + bool impossible_where; StringBuffer<64> table_name; diff --git a/sql/sql_delete.cc b/sql/sql_delete.cc index 602831829d7..30ae60ddc43 100644 --- a/sql/sql_delete.cc +++ b/sql/sql_delete.cc @@ -58,10 +58,12 @@ void Delete_plan::save_query_plan_footprint(QPF_query *query) if (deleting_all_rows) { qpf->deleting_all_rows= true; + qpf->select_type= "SIMPLE"; } else { - Update_plan::save_query_plan_footprint_intern(qpf); + qpf->deleting_all_rows= false; + Update_plan::save_query_plan_footprint_intern(query, qpf); } query->upd_del_plan= qpf; @@ -71,13 +73,14 @@ void Delete_plan::save_query_plan_footprint(QPF_query *query) void Update_plan::save_query_plan_footprint(QPF_query *query) { QPF_update* qpf= new QPF_update; - save_query_plan_footprint_intern(qpf); + save_query_plan_footprint_intern(query, qpf); query->upd_del_plan= qpf; } -void Update_plan::save_query_plan_footprint_intern(QPF_update *qpf) +void Update_plan::save_query_plan_footprint_intern(QPF_query *query, QPF_update *qpf) { + qpf->select_type= "SIMPLE"; qpf->table_name.append(table->pos_in_table_list->alias); if (impossible_where) { @@ -85,8 +88,10 @@ void Update_plan::save_query_plan_footprint_intern(QPF_update *qpf) return; } - // TODO: do we need the following: select_type - //select_lex->set_explain_type(TRUE); + qpf->impossible_where= false; + + select_lex->set_explain_type(TRUE); + qpf->select_type= select_lex->type; /* Set jtype */ if (select && select->quick) @@ -134,6 +139,28 @@ void Update_plan::save_query_plan_footprint_intern(QPF_update *qpf) { explain_append_mrr_info((QUICK_RANGE_SELECT*)select->quick, &qpf->mrr_type); } + + bool skip= updating_a_view; + /* Save subquery children */ + for (SELECT_LEX_UNIT *unit= select_lex->first_inner_unit(); + unit; + unit= unit->next_unit()) + { + if (skip) + { + skip= false; + continue; + } + /* + Display subqueries only if they are not parts of eliminated WHERE/ON + clauses. + */ + if (!(unit->item && unit->item->eliminated)) + qpf->add_child(unit->first_select()->select_number); + + //TODO: temporary?: + unit->save_qpf(query); + } } @@ -194,6 +221,9 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, query_plan.select_lex= &thd->lex->select_lex; query_plan.table= table; + //psergey-todo: Ugly, discuss with Sanja + query_plan.updating_a_view= test(table_list->view); + if (mysql_prepare_delete(thd, table_list, &conds)) DBUG_RETURN(TRUE); @@ -612,7 +642,7 @@ exit_without_my_ok: List dummy; /* note: looked in 5.6 and they too use a dummy list like this */ result->prepare(dummy, &thd->lex->unit); thd->send_explain_fields(result); - int err2= thd->lex->query_plan_footprint->print_explain(result, 0); + int err2= thd->lex->query_plan_footprint->print_explain(result, 0 /* explain flags*/); if (err2) result->abort_result_set(); diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc index 6ad7b288a4b..455ef55944d 100644 --- a/sql/sql_lex.cc +++ b/sql/sql_lex.cc @@ -4337,6 +4337,13 @@ int st_select_lex_unit::save_qpf(QPF_query *output) { //int res= 0; SELECT_LEX *first= first_select(); + + if (!first->next_select()) + { + /* This is a 1-way UNION, i.e. not really a UNION */ + first->save_qpf(output); + return 0; + } QPF_union *qpfu= new QPF_union; /* diff --git a/sql/sql_lex.h b/sql/sql_lex.h index 47d01f2e137..6c7a5ca4d13 100644 --- a/sql/sql_lex.h +++ b/sql/sql_lex.h @@ -730,10 +730,7 @@ public: friend int subselect_union_engine::exec(); List *get_unit_column_types(); -#if 0 - int print_explain(select_result_sink *output, uint8 explain_flags, - bool *printed_anything); -#endif + int save_qpf(QPF_query *output); }; @@ -2379,6 +2376,7 @@ class Update_plan protected: bool impossible_where; public: + bool updating_a_view; TABLE *table; SQL_SELECT *select; uint index; @@ -2396,7 +2394,7 @@ public: void set_impossible_where() { impossible_where= true; } void save_query_plan_footprint(QPF_query *query); - void save_query_plan_footprint_intern(QPF_update *qpf); + void save_query_plan_footprint_intern(QPF_query *query, QPF_update *qpf); virtual ~Update_plan() {} Update_plan() : impossible_where(false), using_filesort(false) {} diff --git a/sql/sql_update.cc b/sql/sql_update.cc index ce56a725567..96f49785a32 100644 --- a/sql/sql_update.cc +++ b/sql/sql_update.cc @@ -314,6 +314,10 @@ int mysql_update(THD *thd, my_error(ER_NON_UPDATABLE_TABLE, MYF(0), table_list->alias, "UPDATE"); DBUG_RETURN(1); } + + //psergey-todo: Ugly, discuss with Sanja + query_plan.updating_a_view= test(table_list->view); + /* Calculate "table->covering_keys" based on the WHERE */ table->covering_keys= table->s->keys_in_use; table->quick_keys.clear_all(); @@ -1013,13 +1017,14 @@ exit_without_my_ok: query_plan.save_query_plan_footprint(thd->lex->query_plan_footprint); select_send *result; - bool printed_anything; + //bool printed_anything; if (!(result= new select_send())) return 1; /* purecov: inspected */ List dummy; /* note: looked in 5.6 and they too use a dummy list like this */ result->prepare(dummy, &thd->lex->unit); thd->send_explain_fields(result); - int err2= thd->lex->print_explain(result, 0 /* explain flags*/, &printed_anything); + //int err2= thd->lex->print_explain(result, 0 /* explain flags*/, &printed_anything); + int err2= thd->lex->query_plan_footprint->print_explain(result, 0 /* explain flags*/); if (err2) result->abort_result_set(); @@ -1498,6 +1503,7 @@ bool mysql_multi_update(THD *thd, { if (explain) { + thd->lex->query_plan_footprint->print_explain(output, 0); output->send_eof(); delete output; } -- cgit v1.2.1 From ab4a13b2b91e260d8c75a3c41b7ff5c24747cee0 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Thu, 20 Jun 2013 22:30:30 +0400 Subject: Switching [EXPLAIN] UPDATE/DELETE to rely on query plan footprints. This requires that subselect's footprints are saved before it is deleted. Attempt to save select's QPF exposes one to a variety of edge cases: - the select may be a UNION's "fake select" which has no valid id - optimization may fail in the middle (but subsequent JOIN::optimize() calls will succeed, despite the fact that there never was a query plan) --- sql/sql_lex.cc | 6 ++++-- sql/sql_select.cc | 38 ++++++++++++++++++++++++++++++++++++-- sql/sql_select.h | 6 ------ 3 files changed, 40 insertions(+), 10 deletions(-) (limited to 'sql') diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc index 455ef55944d..3161dc85fb9 100644 --- a/sql/sql_lex.cc +++ b/sql/sql_lex.cc @@ -4341,7 +4341,8 @@ int st_select_lex_unit::save_qpf(QPF_query *output) if (!first->next_select()) { /* This is a 1-way UNION, i.e. not really a UNION */ - first->save_qpf(output); + if (!output->get_select(first->select_number)) + first->save_qpf(output); return 0; } @@ -4371,7 +4372,8 @@ int st_select_lex_unit::save_qpf(QPF_query *output) for (SELECT_LEX *sl= first; sl; sl= sl->next_select()) { - sl->save_qpf(output); + if (!output->get_select(sl->select_number)) + sl->save_qpf(output); qpfu->add_select(sl->select_number); } diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 91da7526c72..eed6ed5e09f 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -1005,17 +1005,26 @@ err: int JOIN::optimize() { + bool was_optimized= optimized; int res= optimize_inner(); /* If we're inside a non-correlated subquery, this function may be called for the second time after the subquery has been executed and deleted. The second call will not produce a valid query plan, it will short-circuit because optimized==TRUE. + + "was_optimized != optimized" is here to handle this case: + - first optimization starts, gets an error (from a const. cheap + subquery), returns 1 + - another JOIN::optimize() call made, and now join->optimize() will + return 0, even though we never had a query plan. */ - if (!res && have_query_plan != QEP_DELETED) + if (was_optimized != optimized && !res && have_query_plan != QEP_DELETED) have_query_plan= QEP_AVAILABLE; return res; } + + /** global select optimisation. @@ -2301,7 +2310,6 @@ void JOIN::exec() select_lex->select_number)) dbug_serve_apcs(thd, 1); ); - thd->apc_target.disable(); } @@ -11099,7 +11107,33 @@ void JOIN::cleanup(bool full) DBUG_PRINT("enter", ("full %u", (uint) full)); if (full) + { + // + if (select_lex->select_number != UINT_MAX && + select_lex->select_number != INT_MAX /* this is not a UNION's "fake select */ && + have_query_plan != QEP_NOT_PRESENT_YET && + !thd->lex->query_plan_footprint->get_select(select_lex->select_number)) + { + const char *message= NULL; + + if (!table_count || !tables_list || zero_result_cause) + { + /* It's a degenerate join */ + message= zero_result_cause ? zero_result_cause : "No tables used"; + } + + save_qpf(thd->lex->query_plan_footprint, + need_tmp, // need_tmp_table + !skip_sort_order && !no_order && + (order || group_list), // bool need_order + select_distinct, // bool distinct + message); // message + } + + // + have_query_plan= QEP_DELETED; //psergey: this is a problem! + } if (table) { diff --git a/sql/sql_select.h b/sql/sql_select.h index 5ec09fcfcb8..6d4dfed479e 100644 --- a/sql/sql_select.h +++ b/sql/sql_select.h @@ -1462,12 +1462,6 @@ public: { return (unit->item && unit->item->is_in_predicate()); } -/* - int print_explain(select_result_sink *result, uint8 explain_flags, - bool on_the_fly, - bool need_tmp_table, bool need_order, - bool distinct,const char *message); -*/ int save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, bool distinct, const char *message); private: -- cgit v1.2.1 From af5e128e50cac8881f7bfca44cc473600abdce86 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Fri, 21 Jun 2013 13:26:53 +0400 Subject: [SHOW] EXPLAIN UPDATE/DELETE, code re-structuring - Handle statements inside SPs: = regular statements = SET command, which does not have its own statement. - Handle execution of subquery from range optimizer: allocate subquery QPFs on the same MEM_ROOT as the whole query plan was allocated. --- sql/opt_qpf.cc | 15 +++++++++++++-- sql/opt_qpf.h | 2 ++ sql/sp_head.cc | 6 ++++-- sql/sql_lex.cc | 6 +++--- sql/sql_lex.h | 3 ++- sql/sql_parse.cc | 11 +++-------- sql/sql_prepare.cc | 3 +-- sql/sql_select.cc | 9 +++++---- 8 files changed, 33 insertions(+), 22 deletions(-) (limited to 'sql') diff --git a/sql/opt_qpf.cc b/sql/opt_qpf.cc index 425823df9e1..d5a228e8f41 100644 --- a/sql/opt_qpf.cc +++ b/sql/opt_qpf.cc @@ -559,8 +559,19 @@ int QPF_update::print_explain(QPF_query *query, select_result_sink *output, return print_explain_for_children(query, output, explain_flags); } -void delete_qpf_query(QPF_query * query) + +void delete_qpf_query(LEX *lex) +{ + delete lex->query_plan_footprint; + lex->query_plan_footprint= NULL; +} + + +void create_qpf_query(LEX *lex, MEM_ROOT *mem_root) { - delete query; + DBUG_ASSERT(!lex->query_plan_footprint); + lex->query_plan_footprint= new QPF_query; + DBUG_ASSERT(mem_root == current_thd->mem_root); + lex->query_plan_footprint->mem_root= mem_root; } diff --git a/sql/opt_qpf.h b/sql/opt_qpf.h index 53839ecbac8..501ac7c609e 100644 --- a/sql/opt_qpf.h +++ b/sql/opt_qpf.h @@ -214,6 +214,8 @@ public: /* Produce a tabular EXPLAIN output */ int print_explain(select_result_sink *output, uint8 explain_flags); + + MEM_ROOT *mem_root; private: QPF_union *unions[MAX_TABLES]; QPF_select *selects[MAX_TABLES]; diff --git a/sql/sp_head.cc b/sql/sp_head.cc index 3cc3a3893bb..2ad03f3d0dc 100644 --- a/sql/sp_head.cc +++ b/sql/sp_head.cc @@ -2973,6 +2973,7 @@ sp_lex_keeper::reset_lex_and_exec_core(THD *thd, uint *nextp, } reinit_stmt_before_use(thd, m_lex); + // not here, but inside every instr: create_qpf_query(m_lex); if (open_tables) res= instr->exec_open_and_lock_tables(thd, m_lex->query_tables); @@ -3007,8 +3008,7 @@ sp_lex_keeper::reset_lex_and_exec_core(THD *thd, uint *nextp, thd->mdl_context.release_statement_locks(); } - delete_qpf_query(m_lex->query_plan_footprint); - m_lex->query_plan_footprint= NULL; + delete_qpf_query(m_lex); if (m_lex->query_tables_own_last) { @@ -3212,6 +3212,7 @@ sp_instr_set::execute(THD *thd, uint *nextp) int sp_instr_set::exec_core(THD *thd, uint *nextp) { + create_qpf_query(thd->lex, thd->mem_root); int res= thd->spcont->set_variable(thd, m_offset, &m_value); if (res) @@ -3224,6 +3225,7 @@ sp_instr_set::exec_core(THD *thd, uint *nextp) my_error(ER_OUT_OF_RESOURCES, MYF(ME_FATALERROR)); } } + delete_qpf_query(thd->lex); *nextp = m_ip+1; return res; diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc index 3161dc85fb9..df38d9fcdb0 100644 --- a/sql/sql_lex.cc +++ b/sql/sql_lex.cc @@ -4251,7 +4251,7 @@ void st_select_lex::save_qpf(QPF_query *output) msg= "Query plan already deleted"; } set_explain_type(TRUE/* on_the_fly */); - QPF_select *qp_sel= new QPF_select; + QPF_select *qp_sel= new (output->mem_root) QPF_select; qp_sel->select_id= select_number; qp_sel->select_type= type; qp_sel->message= msg; @@ -4346,7 +4346,7 @@ int st_select_lex_unit::save_qpf(QPF_query *output) return 0; } - QPF_union *qpfu= new QPF_union; + QPF_union *qpfu= new (output->mem_root) QPF_union; /* TODO: The following code should be eliminated. If we have a capability to save Query Plan Footprints, we should just save them, and never need to @@ -4361,7 +4361,7 @@ int st_select_lex_unit::save_qpf(QPF_query *output) const char *msg="Query plan already deleted"; first->set_explain_type(TRUE/* on_the_fly */); - QPF_select *qp_sel= new QPF_select; + QPF_select *qp_sel= new (output->mem_root)QPF_select; qp_sel->select_id= first->select_number; qp_sel->select_type= first->type; qp_sel->message= msg; diff --git a/sql/sql_lex.h b/sql/sql_lex.h index 6c7a5ca4d13..7e76c09a4f5 100644 --- a/sql/sql_lex.h +++ b/sql/sql_lex.h @@ -619,7 +619,8 @@ class select_union; class Procedure; class QPF_query; -void delete_qpf_query(QPF_query * query); +void delete_qpf_query(LEX *lex); +void create_qpf_query(LEX *lex, MEM_ROOT *mem_root); class st_select_lex_unit: public st_select_lex_node { protected: diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc index 474d3889b53..6f2f7eaca20 100644 --- a/sql/sql_parse.cc +++ b/sql/sql_parse.cc @@ -598,10 +598,7 @@ static void handle_bootstrap_impl(THD *thd) #if defined(ENABLED_PROFILING) thd->profiling.finish_current_query(); #endif - // - delete thd->lex->query_plan_footprint; - thd->lex->query_plan_footprint= NULL; - // + delete_qpf_query(thd->lex); if (bootstrap_error) break; @@ -1523,8 +1520,7 @@ void log_slow_statement(THD *thd) { DBUG_ENTER("log_slow_statement"); - delete thd->lex->query_plan_footprint; - thd->lex->query_plan_footprint= NULL; + delete_qpf_query(thd->lex); /* The following should never be true with our current code base, @@ -2188,8 +2184,7 @@ mysql_execute_command(THD *thd) thd->mdl_context.release_transactional_locks(); } - DBUG_ASSERT(!thd->lex->query_plan_footprint); - thd->lex->query_plan_footprint= new QPF_query; + create_qpf_query(thd->lex, thd->mem_root); #ifndef DBUG_OFF if (lex->sql_command != SQLCOM_SET_OPTION) diff --git a/sql/sql_prepare.cc b/sql/sql_prepare.cc index d81070b7406..2f62a06f6a4 100644 --- a/sql/sql_prepare.cc +++ b/sql/sql_prepare.cc @@ -3927,8 +3927,7 @@ bool Prepared_statement::execute(String *expanded_query, bool open_cursor) if (! cursor) cleanup_stmt(); //psergey: TODO the "EXECUTE problem" is here - delete_qpf_query(thd->lex->query_plan_footprint); - thd->lex->query_plan_footprint= NULL; + delete_qpf_query(thd->lex); thd->set_statement(&stmt_backup); thd->stmt_arena= old_stmt_arena; diff --git a/sql/sql_select.cc b/sql/sql_select.cc index eed6ed5e09f..bad29d70af9 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -11112,6 +11112,7 @@ void JOIN::cleanup(bool full) if (select_lex->select_number != UINT_MAX && select_lex->select_number != INT_MAX /* this is not a UNION's "fake select */ && have_query_plan != QEP_NOT_PRESENT_YET && + thd->lex->query_plan_footprint && // for "SET" command in SPs. !thd->lex->query_plan_footprint->get_select(select_lex->select_number)) { const char *message= NULL; @@ -22986,7 +22987,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, if (message) { QPF_select *qp_sel; - qp_node= qp_sel= new QPF_select; + qp_node= qp_sel= new (output->mem_root) QPF_select; join->select_lex->set_explain_type(on_the_fly); qp_sel->select_id= join->select_lex->select_number; @@ -22998,7 +22999,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, else if (join->select_lex == join->unit->fake_select_lex) { select_lex->set_explain_type(on_the_fly); - QPF_union *qp_union= new QPF_union; + QPF_union *qp_union= new (output->mem_root) QPF_union; qp_node= qp_union; SELECT_LEX *child; @@ -23018,7 +23019,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, join->select_lex->master_unit()->derived->is_materialized_derived()) { QPF_select *qp_sel; - qp_node= qp_sel= new QPF_select; + qp_node= qp_sel= new (output->mem_root) QPF_select; table_map used_tables=0; if (on_the_fly) @@ -23077,7 +23078,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, tab= pre_sort_join_tab; } - QPF_table_access *qpt= new QPF_table_access; + QPF_table_access *qpt= new (output->mem_root) QPF_table_access; qp_sel->add_table(qpt); /* id */ -- cgit v1.2.1 From cebdf3de2ef2604f3459762fc05a50dd54c1c9f2 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Fri, 21 Jun 2013 22:26:03 +0400 Subject: [SHOW] EXPLAIN UPDATE/DELETE, code re-structuring - Handle another specific case where there the JOIN never had a query plan, but had multiple join->cleanup(full=true) calls - The idea that there can only be MAX_TABLES subuqeries/unions was wrong. Switch QPF_query to using a Dynamic_array. = make Dynamic_array template support size growth. its underlying DYNAMIC_ARRAY supports it. (this part will need more polishing) --- sql/opt_qpf.cc | 42 ++++++++++++++++++++++++++++-------------- sql/opt_qpf.h | 8 ++++++-- sql/sql_array.h | 18 ++++++++++++++++++ sql/sql_select.cc | 3 +++ 4 files changed, 55 insertions(+), 16 deletions(-) (limited to 'sql') diff --git a/sql/opt_qpf.cc b/sql/opt_qpf.cc index d5a228e8f41..204a7e00350 100644 --- a/sql/opt_qpf.cc +++ b/sql/opt_qpf.cc @@ -13,8 +13,8 @@ QPF_query::QPF_query() { upd_del_plan= NULL; - memset(&unions, 0, sizeof(unions)); - memset(&selects, 0, sizeof(selects)); + //memset(&unions, 0, sizeof(unions)); + //memset(&selects, 0, sizeof(selects)); } @@ -22,25 +22,30 @@ QPF_query::~QPF_query() { delete upd_del_plan; uint i; - for (i=0 ; i < MAX_TABLES; i++) - delete unions[i]; - for (i=0 ; i < MAX_TABLES; i++) - delete selects[i]; + for (i= 0 ; i < unions.elements(); i++) + delete unions.at(i); + for (i= 0 ; i < selects.elements(); i++) + delete selects.at(i); } QPF_node *QPF_query::get_node(uint select_id) { - if (unions[select_id]) - return unions[select_id]; + QPF_union *u; + if ((u= get_union(select_id))) + return u; else - return selects[select_id]; + return get_select(select_id); } +QPF_union *QPF_query::get_union(uint select_id) +{ + return (unions.elements() > select_id) ? unions.at(select_id) : NULL; +} QPF_select *QPF_query::get_select(uint select_id) { - return selects[select_id]; + return (selects.elements() > select_id) ? selects.at(select_id) : NULL; } @@ -49,8 +54,13 @@ void QPF_query::add_node(QPF_node *node) if (node->get_type() == QPF_node::QPF_UNION) { QPF_union *u= (QPF_union*)node; - DBUG_ASSERT(!unions[u->get_select_id()]); - unions[u->get_select_id()]= u; + uint select_id= u->get_select_id(); + DBUG_ASSERT(!get_union(select_id)); + + if (unions.elements() <= select_id) + unions.resize(max(select_id+1, unions.elements()*2), NULL); + + unions.at(select_id)= u; } else { @@ -62,8 +72,12 @@ void QPF_query::add_node(QPF_node *node) } else { - DBUG_ASSERT(!selects[sel->select_id]); - selects[sel->select_id] = sel; + uint select_id= sel->select_id; + DBUG_ASSERT(!get_select(select_id)); + + if (selects.elements() <= select_id) + selects.resize(max(select_id+1, selects.elements()*2), NULL); + selects.at(select_id)= sel; } } } diff --git a/sql/opt_qpf.h b/sql/opt_qpf.h index 501ac7c609e..1944f79254d 100644 --- a/sql/opt_qpf.h +++ b/sql/opt_qpf.h @@ -209,6 +209,8 @@ public: /* This will return a select (even if there is a union with this id) */ QPF_select *get_select(uint select_id); + QPF_union *get_union(uint select_id); + /* QPF_delete inherits from QPF_update */ QPF_update *upd_del_plan; @@ -217,8 +219,10 @@ public: MEM_ROOT *mem_root; private: - QPF_union *unions[MAX_TABLES]; - QPF_select *selects[MAX_TABLES]; + Dynamic_array unions; + Dynamic_array selects; + //QPF_union *unions[MAX_TABLES]; + //QPF_select *selects[MAX_TABLES]; }; diff --git a/sql/sql_array.h b/sql/sql_array.h index 43ca4ef4219..18f1fbd9f2f 100644 --- a/sql/sql_array.h +++ b/sql/sql_array.h @@ -106,6 +106,7 @@ public: Elem& at(size_t idx) { + DBUG_ASSERT(idx < array.elements); return *(((Elem*)array.buffer) + idx); } @@ -139,6 +140,23 @@ public: array.elements= n; } + bool resize(size_t new_size, Elem default_val) + { + size_t old_size= elements(); + if (allocate_dynamic(&array, new_size)) + return true; + + if (new_size > old_size) + { + set_dynamic(&array, (uchar*)&default_val, new_size - 1); + /*for (size_t i= old_size; i != new_size; i++) + { + at(i)= default_val; + }*/ + } + return false; + } + ~Dynamic_array() { delete_dynamic(&array); diff --git a/sql/sql_select.cc b/sql/sql_select.cc index bad29d70af9..1b98d0b12ee 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -11112,6 +11112,9 @@ void JOIN::cleanup(bool full) if (select_lex->select_number != UINT_MAX && select_lex->select_number != INT_MAX /* this is not a UNION's "fake select */ && have_query_plan != QEP_NOT_PRESENT_YET && + have_query_plan != QEP_DELETED && // this happens when there was no QEP ever, but then + //cleanup() is called multiple times + thd->lex->query_plan_footprint && // for "SET" command in SPs. !thd->lex->query_plan_footprint->get_select(select_lex->select_number)) { -- cgit v1.2.1 From 79392b9383921cb1d48ca0defb8715f7385af0e8 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Fri, 21 Jun 2013 22:45:54 +0400 Subject: [SHOW] EXPLAIN UPDATE/DELETE, code re-structuring - Support "using index for group-by (scanning) " queries --- sql/opt_qpf.cc | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'sql') diff --git a/sql/opt_qpf.cc b/sql/opt_qpf.cc index 204a7e00350..309e24471eb 100644 --- a/sql/opt_qpf.cc +++ b/sql/opt_qpf.cc @@ -497,6 +497,12 @@ void QPF_table_access::append_tag_name(String *str, enum Extra_tag tag) str->append(extra_tag_text[tag]); break; } + case ET_USING_INDEX_FOR_GROUP_BY: + { + str->append(extra_tag_text[tag]); + str->append(loose_scan_type); + break; + } default: str->append(extra_tag_text[tag]); } -- cgit v1.2.1 From 99a8bfe68cdd6411ed24b3fa465d5dd4b70be6dc Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Thu, 27 Jun 2013 01:00:22 +0400 Subject: [SHOW] EXPLAIN UPDATE/DELETE, code re-structuring - Update view.result (old EXPLAIN didn't match the execution) - Put in a stub code to work around the SELECT ... UNION SELECT ... ORDER BY (subuqery) problem --- sql/sql_delete.cc | 4 +- sql/sql_lex.cc | 182 +++++---------- sql/sql_lex.h | 2 + sql/sql_select.cc | 652 +++++------------------------------------------------- sql/sql_union.cc | 6 + 5 files changed, 121 insertions(+), 725 deletions(-) (limited to 'sql') diff --git a/sql/sql_delete.cc b/sql/sql_delete.cc index 30ae60ddc43..50401e2af46 100644 --- a/sql/sql_delete.cc +++ b/sql/sql_delete.cc @@ -159,7 +159,9 @@ void Update_plan::save_query_plan_footprint_intern(QPF_query *query, QPF_update qpf->add_child(unit->first_select()->select_number); //TODO: temporary?: - unit->save_qpf(query); + // A: yes. optimizing children subqueries has caused them to save QPFs, + // automatically. + //unit->save_qpf(query); } } diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc index df38d9fcdb0..c453a599dce 100644 --- a/sql/sql_lex.cc +++ b/sql/sql_lex.cc @@ -4172,29 +4172,32 @@ bool st_select_lex::is_merged_child_of(st_select_lex *ancestor) return all_merged; } +/* + This is used by SHOW EXPLAIN. It assuses query plan has been already + collected into QPF structures and we only need to print it out. +*/ int LEX::print_explain(select_result_sink *output, uint8 explain_flags, - bool *printed_anything) + bool *printed_anything) //TODO: remove printed_anything { - /* if (upd_del_plan) + int res; + if (query_plan_footprint) { - upd_del_plan->print_explain(output, explain_flags, printed_anything); - return 0; - }*/ - //int res= unit.print_explain(output, explain_flags, printed_anything); - - //psergey-todo: here, we should make Query Plan Footprint, and then produce - // an EXPLAIN output from it. - /* - The new, QueryPlanFootprint way: - */ - QPF_query qpf; - unit.save_qpf(&qpf); - //return res; - return 0; + res= query_plan_footprint->print_explain(output, explain_flags); + *printed_anything= true; + } + else + { + res= 0; + *printed_anything= false; + } + return res; } +/* + +*/ void st_select_lex::save_qpf(QPF_query *output) { int res; @@ -4261,92 +4264,12 @@ err: return ;//res; } -#if 0 -int st_select_lex::print_explain(select_result_sink *output, - uint8 explain_flags, - bool *printed_anything) -{ - int res; - if (join && join->have_query_plan == JOIN::QEP_AVAILABLE) - { - /* - There is a number of reasons join can be marked as degenerate, so all - three conditions below can happen simultaneously, or individually: - */ - *printed_anything= TRUE; - if (!join->table_count || !join->tables_list || join->zero_result_cause) - { - /* It's a degenerate join */ - const char *cause= join->zero_result_cause ? join-> zero_result_cause : - "No tables used"; - res= join->print_explain(output, explain_flags, TRUE, FALSE, FALSE, - FALSE, cause); - } - else - { - res= join->print_explain(output, explain_flags, TRUE, - join->need_tmp, // need_tmp_table - !join->skip_sort_order && !join->no_order && - (join->order || join->group_list), // bool need_order - join->select_distinct, // bool distinct - NULL); //const char *message - } - if (res) - goto err; - - for (SELECT_LEX_UNIT *unit= join->select_lex->first_inner_unit(); - unit; - unit= unit->next_unit()) - { - /* - Display subqueries only if they are not parts of eliminated WHERE/ON - clauses. - */ - if (!(unit->item && unit->item->eliminated)) - { - if ((res= unit->print_explain(output, explain_flags, printed_anything))) - goto err; - } - } - } - else - { - const char *msg; - if (!join) - DBUG_ASSERT(0); /* Seems not to be possible */ - - /* Not printing anything useful, don't touch *printed_anything here */ - if (join->have_query_plan == JOIN::QEP_NOT_PRESENT_YET) - msg= "Not yet optimized"; - else - { - DBUG_ASSERT(join->have_query_plan == JOIN::QEP_DELETED); - msg= "Query plan already deleted"; - } - set_explain_type(TRUE/* on_the_fly */); - res= print_explain_message_line(output, 0/*options*/, select_number, type, - msg); - } -err: - return res; -} -#endif - -int st_select_lex_unit::save_qpf(QPF_query *output) +int st_select_lex_unit::save_union_qpf(QPF_query *output) { - //int res= 0; SELECT_LEX *first= first_select(); - - if (!first->next_select()) - { - /* This is a 1-way UNION, i.e. not really a UNION */ - if (!output->get_select(first->select_number)) - first->save_qpf(output); - return 0; - } - QPF_union *qpfu= new (output->mem_root) QPF_union; + /* TODO: The following code should be eliminated. If we have a capability to save Query Plan Footprints, we should just save them, and never need to @@ -4380,53 +4303,48 @@ int st_select_lex_unit::save_qpf(QPF_query *output) // Save the UNION node output->add_node(qpfu); -#if 0 - /* Note: fake_select_lex->join may be NULL or non-NULL at this point */ + qpfu->fake_select_type= "UNION RESULT"; + qpfu->using_filesort= test(global_parameters->order_list.first); + return 0; +} + + +int st_select_lex_unit::save_union_qpf_part2(QPF_query *output) +{ + QPF_union *qpfu= output->get_union(first_select()->select_number); if (fake_select_lex) { - res= print_fake_select_lex_join(output, TRUE /* on the fly */, - fake_select_lex, explain_flags); + for (SELECT_LEX_UNIT *unit= fake_select_lex->first_inner_unit(); + unit; unit= unit->next_unit()) + { + if (!(unit->item && unit->item->eliminated)) + { + qpfu->add_child(unit->first_select()->select_number); + } + } } - return res; -#endif return 0; } -#if 0 -int st_select_lex_unit::print_explain(select_result_sink *output, - uint8 explain_flags, bool *printed_anything) + +int st_select_lex_unit::save_qpf(QPF_query *output) { - int res= 0; + //int res= 0; SELECT_LEX *first= first_select(); - - if (first && !first->next_select() && !first->join) - { - /* - If there is only one child, 'first', and it has join==NULL, emit "not in - EXPLAIN state" error. - */ - const char *msg="Query plan already deleted"; - first->set_explain_type(TRUE/* on_the_fly */); - res= print_explain_message_line(output, 0/*options*/, first->select_number, - first->type, msg); - return res; - } - for (SELECT_LEX *sl= first; sl; sl= sl->next_select()) + if (!first->next_select()) { - if ((res= sl->print_explain(output, explain_flags, printed_anything))) - break; + /* This is a 1-way UNION, i.e. not really a UNION */ + if (!output->get_select(first->select_number)) + first->save_qpf(output); + return 0; } - /* Note: fake_select_lex->join may be NULL or non-NULL at this point */ - if (fake_select_lex) - { - res= print_fake_select_lex_join(output, TRUE /* on the fly */, - fake_select_lex, explain_flags); - } - return res; + save_union_qpf(output); + + return 0; } -#endif + /** A routine used by the parser to decide whether we are specifying a full diff --git a/sql/sql_lex.h b/sql/sql_lex.h index 7e76c09a4f5..77abc46d30b 100644 --- a/sql/sql_lex.h +++ b/sql/sql_lex.h @@ -733,6 +733,8 @@ public: List *get_unit_column_types(); int save_qpf(QPF_query *output); + int save_union_qpf(QPF_query *output); + int save_union_qpf_part2(QPF_query *output); }; typedef class st_select_lex_unit SELECT_LEX_UNIT; diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 1b98d0b12ee..5e20d2faf24 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -1002,6 +1002,7 @@ err: DBUG_RETURN(res); /* purecov: inspected */ } +void join_save_qpf(JOIN *join); int JOIN::optimize() { @@ -1020,7 +1021,10 @@ int JOIN::optimize() return 0, even though we never had a query plan. */ if (was_optimized != optimized && !res && have_query_plan != QEP_DELETED) + { have_query_plan= QEP_AVAILABLE; + join_save_qpf(this); + } return res; } @@ -1611,8 +1615,10 @@ TODO: make view to decide if it is possible to write to WHERE directly or make S JOIN_TAB *tab= &join_tab[const_tables]; bool all_order_fields_used; if (order) + { skip_sort_order= test_if_skip_sort_order(tab, order, select_limit, 1, &tab->table->keys_in_use_for_order_by); + } if ((group_list=create_distinct_group(thd, select_lex->ref_pointer_array, order, fields_list, all_fields, &all_order_fields_used))) @@ -2289,11 +2295,48 @@ JOIN::save_join_tab() } +void join_save_qpf(JOIN *join) +{ + THD *thd= join->thd; +//TODO: why not call st_select_lex::save_qpf here? + + if (join->select_lex->select_number != UINT_MAX && + join->select_lex->select_number != INT_MAX /* this is not a UNION's "fake select */ && + join->have_query_plan != JOIN::QEP_NOT_PRESENT_YET && + join->have_query_plan != JOIN::QEP_DELETED && // this happens when there was no QEP ever, but then + //cleanup() is called multiple times + + thd->lex->query_plan_footprint && // for "SET" command in SPs. + !thd->lex->query_plan_footprint->get_select(join->select_lex->select_number)) + { + const char *message= NULL; + + if (!join->table_count || !join->tables_list || join->zero_result_cause) + { + /* It's a degenerate join */ + message= join->zero_result_cause ? join->zero_result_cause : "No tables used"; + } + + join->save_qpf(thd->lex->query_plan_footprint, + join->need_tmp, // need_tmp_table + !join->skip_sort_order && !join->no_order && + (join->order || join->group_list), // bool need_order + join->select_distinct, // bool distinct + message); // message + } +} + + void JOIN::exec() { /* Enable SHOW EXPLAIN only if we're in the top-level query. */ + + /* + psergey: we can produce SHOW explain at this point. This means, we're ready + to save the query plan. + */ thd->apc_target.enable(); DBUG_EXECUTE_IF("show_explain_probe_join_exec_start", if (dbug_user_var_equals_int(thd, @@ -11109,6 +11152,7 @@ void JOIN::cleanup(bool full) if (full) { // +#if 0 if (select_lex->select_number != UINT_MAX && select_lex->select_number != INT_MAX /* this is not a UNION's "fake select */ && have_query_plan != QEP_NOT_PRESENT_YET && @@ -11133,7 +11177,7 @@ void JOIN::cleanup(bool full) select_distinct, // bool distinct message); // message } - +#endif // have_query_plan= QEP_DELETED; //psergey: this is a problem! @@ -22352,589 +22396,6 @@ void explain_append_mrr_info(QUICK_RANGE_SELECT *quick, String *res) } -/** - EXPLAIN handling. - - Produce lines explaining execution of *this* select (not including children - selects) - @param on_the_fly TRUE <=> we're being executed on-the-fly, so don't make - modifications to any select's data structures - - psergey-todo: should this produce a data structure with a query plan? Or, the - data structure with the query plan should be produced in any way? -*/ -#if 0 -int JOIN::print_explain(select_result_sink *result, uint8 explain_flags, - bool on_the_fly, - bool need_tmp_table, bool need_order, - bool distinct, const char *message) -{ - List field_list; - List item_list; - JOIN *join= this; /* Legacy: this code used to be a non-member function */ - THD *thd=join->thd; - Item *item_null= new Item_null(); - CHARSET_INFO *cs= system_charset_info; - int quick_type; - int error= 0; - DBUG_ENTER("JOIN::print_explain"); - DBUG_PRINT("info", ("Select 0x%lx, type %s, message %s", - (ulong)join->select_lex, join->select_lex->type, - message ? message : "NULL")); - DBUG_ASSERT(on_the_fly? have_query_plan == QEP_AVAILABLE: TRUE); - /* Don't log this into the slow query log */ - - if (!on_the_fly) - { - thd->server_status&= ~(SERVER_QUERY_NO_INDEX_USED | SERVER_QUERY_NO_GOOD_INDEX_USED); - join->unit->offset_limit_cnt= 0; - } - - /* - NOTE: the number/types of items pushed into item_list must be in sync with - EXPLAIN column types as they're "defined" in THD::send_explain_fields() - */ - if (message) - { - if (on_the_fly) - join->select_lex->set_explain_type(on_the_fly); - - if (print_explain_message_line(result, explain_flags, - join->select_lex->select_number, - join->select_lex->type, message)) - error= 1; - - } - else if (join->select_lex == join->unit->fake_select_lex) - { - if (print_fake_select_lex_join(result, on_the_fly, - join->select_lex, - explain_flags)) - error= 1; - } - else if (!join->select_lex->master_unit()->derived || - join->select_lex->master_unit()->derived->is_materialized_derived()) - { - table_map used_tables=0; - - if (on_the_fly) - join->select_lex->set_explain_type(on_the_fly); - - bool printing_materialize_nest= FALSE; - uint select_id= join->select_lex->select_number; - - JOIN_TAB* const first_top_tab= first_breadth_first_tab(join, WALK_OPTIMIZATION_TABS); - - for (JOIN_TAB *tab= first_breadth_first_tab(join, WALK_OPTIMIZATION_TABS); tab; - tab= next_breadth_first_tab(join, WALK_OPTIMIZATION_TABS, tab)) - { - if (tab->bush_root_tab) - { - JOIN_TAB *first_sibling= tab->bush_root_tab->bush_children->start; - select_id= first_sibling->emb_sj_nest->sj_subq_pred->get_identifier(); - printing_materialize_nest= TRUE; - } - - TABLE *table=tab->table; - TABLE_LIST *table_list= tab->table->pos_in_table_list; - char buff[512]; - char buff1[512], buff2[512], buff3[512], buff4[512]; - char keylen_str_buf[64]; - my_bool key_read; - String extra(buff, sizeof(buff),cs); - char table_name_buffer[SAFE_NAME_LEN]; - String tmp1(buff1,sizeof(buff1),cs); - String tmp2(buff2,sizeof(buff2),cs); - String tmp3(buff3,sizeof(buff3),cs); - String tmp4(buff4,sizeof(buff4),cs); - char hash_key_prefix[]= "#hash#"; - KEY *key_info= 0; - uint key_len= 0; - bool is_hj= tab->type == JT_HASH || tab->type ==JT_HASH_NEXT; - - extra.length(0); - tmp1.length(0); - tmp2.length(0); - tmp3.length(0); - tmp4.length(0); - quick_type= -1; - QUICK_SELECT_I *quick= NULL; - JOIN_TAB *saved_join_tab= NULL; - - /* Don't show eliminated tables */ - if (table->map & join->eliminated_tables) - { - used_tables|=table->map; - continue; - } - - if (join->table_access_tabs == join->join_tab && - tab == (first_top_tab + join->const_tables) && pre_sort_join_tab) - { - saved_join_tab= tab; - tab= pre_sort_join_tab; - } - - item_list.empty(); - /* id */ - item_list.push_back(new Item_uint((uint32)select_id)); - /* select_type */ - const char* stype= printing_materialize_nest? "MATERIALIZED" : - join->select_lex->type; - item_list.push_back(new Item_string(stype, strlen(stype), cs)); - - enum join_type tab_type= tab->type; - if ((tab->type == JT_ALL || tab->type == JT_HASH) && - tab->select && tab->select->quick && tab->use_quick != 2) - { - quick= tab->select->quick; - quick_type= tab->select->quick->get_type(); - if ((quick_type == QUICK_SELECT_I::QS_TYPE_INDEX_MERGE) || - (quick_type == QUICK_SELECT_I::QS_TYPE_INDEX_INTERSECT) || - (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_INTERSECT) || - (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_UNION)) - tab_type= tab->type == JT_ALL ? JT_INDEX_MERGE : JT_HASH_INDEX_MERGE; - else - tab_type= tab->type == JT_ALL ? JT_RANGE : JT_HASH_RANGE; - } - - /* table */ - if (table->derived_select_number) - { - /* Derived table name generation */ - int len= my_snprintf(table_name_buffer, sizeof(table_name_buffer)-1, - "", - table->derived_select_number); - item_list.push_back(new Item_string(table_name_buffer, len, cs)); - } - else if (tab->bush_children) - { - JOIN_TAB *ctab= tab->bush_children->start; - /* table */ - int len= my_snprintf(table_name_buffer, - sizeof(table_name_buffer)-1, - "", - ctab->emb_sj_nest->sj_subq_pred->get_identifier()); - item_list.push_back(new Item_string(table_name_buffer, len, cs)); - } - else - { - TABLE_LIST *real_table= table->pos_in_table_list; - item_list.push_back(new Item_string(real_table->alias, - strlen(real_table->alias), cs)); - } - /* "partitions" column */ - if (explain_flags & DESCRIBE_PARTITIONS) - { -#ifdef WITH_PARTITION_STORAGE_ENGINE - partition_info *part_info; - if (!table->derived_select_number && - (part_info= table->part_info)) - { - Item_string *item_str= new Item_string(cs); - make_used_partitions_str(part_info, &item_str->str_value); - item_list.push_back(item_str); - } - else - item_list.push_back(item_null); -#else - /* just produce empty column if partitioning is not compiled in */ - item_list.push_back(item_null); -#endif - } - /* "type" column */ - item_list.push_back(new Item_string(join_type_str[tab_type], - strlen(join_type_str[tab_type]), - cs)); - /* Build "possible_keys" value and add it to item_list */ - if (!tab->keys.is_clear_all()) - { - uint j; - for (j=0 ; j < table->s->keys ; j++) - { - if (tab->keys.is_set(j)) - { - if (tmp1.length()) - tmp1.append(','); - tmp1.append(table->key_info[j].name, - strlen(table->key_info[j].name), - system_charset_info); - } - } - } - if (tmp1.length()) - item_list.push_back(new Item_string(tmp1.ptr(),tmp1.length(),cs)); - else - item_list.push_back(item_null); - - /* Build "key", "key_len", and "ref" values and add them to item_list */ - if (tab_type == JT_NEXT) - { - key_info= table->key_info+tab->index; - key_len= key_info->key_length; - } - else if (tab->ref.key_parts) - { - key_info= tab->get_keyinfo_by_key_no(tab->ref.key); - key_len= tab->ref.key_length; - } - if (key_info) - { - register uint length; - if (is_hj) - tmp2.append(hash_key_prefix, strlen(hash_key_prefix), cs); - tmp2.append(key_info->name, strlen(key_info->name), cs); - length= (longlong10_to_str(key_len, keylen_str_buf, 10) - - keylen_str_buf); - tmp3.append(keylen_str_buf, length, cs); - if (tab->ref.key_parts && tab_type != JT_FT) - { - store_key **ref=tab->ref.key_copy; - for (uint kp= 0; kp < tab->ref.key_parts; kp++) - { - if (tmp4.length()) - tmp4.append(','); - - if ((key_part_map(1) << kp) & tab->ref.const_ref_part_map) - tmp4.append("const"); - else - { - tmp4.append((*ref)->name(), strlen((*ref)->name()), cs); - ref++; - } - } - } - } - if (is_hj && tab_type != JT_HASH) - { - tmp2.append(':'); - tmp3.append(':'); - } - if (tab_type == JT_HASH_NEXT) - { - register uint length; - key_info= table->key_info+tab->index; - key_len= key_info->key_length; - tmp2.append(key_info->name, strlen(key_info->name), cs); - length= (longlong10_to_str(key_len, keylen_str_buf, 10) - - keylen_str_buf); - tmp3.append(keylen_str_buf, length, cs); - } - if (tab->type != JT_CONST && tab->select && quick) - tab->select->quick->add_keys_and_lengths(&tmp2, &tmp3); - if (key_info || (tab->select && quick)) - { - if (tmp2.length()) - item_list.push_back(new Item_string(tmp2.ptr(),tmp2.length(),cs)); - else - item_list.push_back(item_null); - if (tmp3.length()) - item_list.push_back(new Item_string(tmp3.ptr(),tmp3.length(),cs)); - else - item_list.push_back(item_null); - if (key_info && tab_type != JT_NEXT) - item_list.push_back(new Item_string(tmp4.ptr(),tmp4.length(),cs)); - else - item_list.push_back(item_null); - } - else - { - if (table_list && /* SJM bushes don't have table_list */ - table_list->schema_table && - table_list->schema_table->i_s_requested_object & OPTIMIZE_I_S_TABLE) - { - const char *tmp_buff; - int f_idx; - if (table_list->has_db_lookup_value) - { - f_idx= table_list->schema_table->idx_field1; - tmp_buff= table_list->schema_table->fields_info[f_idx].field_name; - tmp2.append(tmp_buff, strlen(tmp_buff), cs); - } - if (table_list->has_table_lookup_value) - { - if (table_list->has_db_lookup_value) - tmp2.append(','); - f_idx= table_list->schema_table->idx_field2; - tmp_buff= table_list->schema_table->fields_info[f_idx].field_name; - tmp2.append(tmp_buff, strlen(tmp_buff), cs); - } - if (tmp2.length()) - item_list.push_back(new Item_string(tmp2.ptr(),tmp2.length(),cs)); - else - item_list.push_back(item_null); - } - else - item_list.push_back(item_null); - item_list.push_back(item_null); - item_list.push_back(item_null); - } - - /* Add "rows" field to item_list. */ - if (table_list /* SJM bushes don't have table_list */ && - table_list->schema_table) - { - /* in_rows */ - if (explain_flags & DESCRIBE_EXTENDED) - item_list.push_back(item_null); - /* rows */ - item_list.push_back(item_null); - } - else - { - ha_rows examined_rows= tab->get_examined_rows(); - - item_list.push_back(new Item_int((longlong) (ulonglong) examined_rows, - MY_INT64_NUM_DECIMAL_DIGITS)); - - /* Add "filtered" field to item_list. */ - if (explain_flags & DESCRIBE_EXTENDED) - { - float f= 0.0; - if (examined_rows) - { - double pushdown_cond_selectivity= tab->cond_selectivity; - if (pushdown_cond_selectivity == 1.0) - f= (float) (100.0 * tab->records_read / examined_rows); - else - f= (float) (100.0 * pushdown_cond_selectivity); - } - set_if_smaller(f, 100.0); - item_list.push_back(new Item_float(f, 2)); - } - } - - /* Build "Extra" field and add it to item_list. */ - key_read=table->key_read; - if ((tab_type == JT_NEXT || tab_type == JT_CONST) && - table->covering_keys.is_set(tab->index)) - key_read=1; - if (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_INTERSECT && - !((QUICK_ROR_INTERSECT_SELECT*)quick)->need_to_fetch_row) - key_read=1; - - if (tab->info) - { - const char *reason; - switch (tab->info) { - case ET_CONST_ROW_NOT_FOUND: - reason= "const row not found"; - break; - case ET_UNIQUE_ROW_NOT_FOUND: - reason= "unique row not found"; - break; - case ET_IMPOSSIBLE_ON_CONDITION: - reason= "Impossible ON condition"; - break; - default: - DBUG_ASSERT(0); - } - item_list.push_back(new Item_string(reason,strlen(reason),cs)); - } - else if (tab->packed_info & TAB_INFO_HAVE_VALUE) - { - if (tab->packed_info & TAB_INFO_USING_INDEX) - extra.append(STRING_WITH_LEN("; Using index")); - if (tab->packed_info & TAB_INFO_USING_WHERE) - extra.append(STRING_WITH_LEN("; Using where")); - if (tab->packed_info & TAB_INFO_FULL_SCAN_ON_NULL) - extra.append(STRING_WITH_LEN("; Full scan on NULL key")); - /* Skip initial "; "*/ - const char *str= extra.ptr(); - uint32 len= extra.length(); - if (len) - { - str += 2; - len -= 2; - } - item_list.push_back(new Item_string(str, len, cs)); - } - else - { - uint keyno= MAX_KEY; - if (tab->ref.key_parts) - keyno= tab->ref.key; - else if (tab->select && quick) - keyno = quick->index; - - if (keyno != MAX_KEY && keyno == table->file->pushed_idx_cond_keyno && - table->file->pushed_idx_cond) - extra.append(STRING_WITH_LEN("; Using index condition")); - else if (tab->cache_idx_cond) - extra.append(STRING_WITH_LEN("; Using index condition(BKA)")); - - if (quick_type == QUICK_SELECT_I::QS_TYPE_ROR_UNION || - quick_type == QUICK_SELECT_I::QS_TYPE_ROR_INTERSECT || - quick_type == QUICK_SELECT_I::QS_TYPE_INDEX_INTERSECT || - quick_type == QUICK_SELECT_I::QS_TYPE_INDEX_MERGE) - { - extra.append(STRING_WITH_LEN("; Using ")); - tab->select->quick->add_info_string(&extra); - } - if (tab->select) - { - if (tab->use_quick == 2) - { - /* 4 bits per 1 hex digit + terminating '\0' */ - char buf[MAX_KEY / 4 + 1]; - extra.append(STRING_WITH_LEN("; Range checked for each " - "record (index map: 0x")); - extra.append(tab->keys.print(buf)); - extra.append(')'); - } - else if (tab->select->cond) - { - const COND *pushed_cond= tab->table->file->pushed_cond; - - if (((thd->variables.optimizer_switch & - OPTIMIZER_SWITCH_ENGINE_CONDITION_PUSHDOWN) || - (tab->table->file->ha_table_flags() & - HA_MUST_USE_TABLE_CONDITION_PUSHDOWN)) && - pushed_cond) - { - extra.append(STRING_WITH_LEN("; Using where with pushed " - "condition")); - if (explain_flags & DESCRIBE_EXTENDED) - { - extra.append(STRING_WITH_LEN(": ")); - ((COND *)pushed_cond)->print(&extra, QT_ORDINARY); - } - } - else - extra.append(STRING_WITH_LEN("; Using where")); - } - } - if (table_list /* SJM bushes don't have table_list */ && - table_list->schema_table && - table_list->schema_table->i_s_requested_object & OPTIMIZE_I_S_TABLE) - { - if (!table_list->table_open_method) - extra.append(STRING_WITH_LEN("; Skip_open_table")); - else if (table_list->table_open_method == OPEN_FRM_ONLY) - extra.append(STRING_WITH_LEN("; Open_frm_only")); - else - extra.append(STRING_WITH_LEN("; Open_full_table")); - if (table_list->has_db_lookup_value && - table_list->has_table_lookup_value) - extra.append(STRING_WITH_LEN("; Scanned 0 databases")); - else if (table_list->has_db_lookup_value || - table_list->has_table_lookup_value) - extra.append(STRING_WITH_LEN("; Scanned 1 database")); - else - extra.append(STRING_WITH_LEN("; Scanned all databases")); - } - if (key_read) - { - if (quick_type == QUICK_SELECT_I::QS_TYPE_GROUP_MIN_MAX) - { - QUICK_GROUP_MIN_MAX_SELECT *qgs= - (QUICK_GROUP_MIN_MAX_SELECT *) tab->select->quick; - extra.append(STRING_WITH_LEN("; Using index for group-by")); - qgs->append_loose_scan_type(&extra); - } - else - extra.append(STRING_WITH_LEN("; Using index")); - } - if (table->reginfo.not_exists_optimize) - extra.append(STRING_WITH_LEN("; Not exists")); - - /* - if (quick_type == QUICK_SELECT_I::QS_TYPE_RANGE && - !(((QUICK_RANGE_SELECT*)(tab->select->quick))->mrr_flags & - HA_MRR_USE_DEFAULT_IMPL)) - { - extra.append(STRING_WITH_LEN("; Using MRR")); - } - */ - if (quick_type == QUICK_SELECT_I::QS_TYPE_RANGE) - { - explain_append_mrr_info((QUICK_RANGE_SELECT*)(tab->select->quick), - &extra); - } - - if (need_tmp_table) - { - need_tmp_table=0; - extra.append(STRING_WITH_LEN("; Using temporary")); - } - if (need_order) - { - need_order=0; - extra.append(STRING_WITH_LEN("; Using filesort")); - } - if (distinct & test_all_bits(used_tables, - join->select_list_used_tables)) - extra.append(STRING_WITH_LEN("; Distinct")); - if (tab->loosescan_match_tab) - { - extra.append(STRING_WITH_LEN("; LooseScan")); - } - - if (tab->first_weedout_table) - extra.append(STRING_WITH_LEN("; Start temporary")); - if (tab->check_weed_out_table) - extra.append(STRING_WITH_LEN("; End temporary")); - else if (tab->do_firstmatch) - { - if (tab->do_firstmatch == /*join->join_tab*/ first_top_tab - 1) - extra.append(STRING_WITH_LEN("; FirstMatch")); - else - { - extra.append(STRING_WITH_LEN("; FirstMatch(")); - TABLE *prev_table=tab->do_firstmatch->table; - if (prev_table->derived_select_number) - { - char namebuf[NAME_LEN]; - /* Derived table name generation */ - int len= my_snprintf(namebuf, sizeof(namebuf)-1, - "", - prev_table->derived_select_number); - extra.append(namebuf, len); - } - else - extra.append(prev_table->pos_in_table_list->alias); - extra.append(STRING_WITH_LEN(")")); - } - } - - for (uint part= 0; part < tab->ref.key_parts; part++) - { - if (tab->ref.cond_guards[part]) - { - extra.append(STRING_WITH_LEN("; Full scan on NULL key")); - break; - } - } - - if (tab->cache) - { - extra.append(STRING_WITH_LEN("; Using join buffer")); - tab->cache->print_explain_comment(&extra); - } - - /* Skip initial "; "*/ - const char *str= extra.ptr(); - uint32 len= extra.length(); - if (len) - { - str += 2; - len -= 2; - } - item_list.push_back(new Item_string(str, len, cs)); - } - - if (saved_join_tab) - tab= saved_join_tab; - - // For next iteration - used_tables|=table->map; - if (result->send_data(item_list)) - error= 1; - } - } - DBUG_RETURN(error); -} -#endif ///////////////////////////////////////////////////////////////////////////////////////////////// void QPF_table_access::push_extra(enum Extra_tag extra_tag) { @@ -23001,6 +22462,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, } else if (join->select_lex == join->unit->fake_select_lex) { +#if 0 select_lex->set_explain_type(on_the_fly); QPF_union *qp_union= new (output->mem_root) QPF_union; qp_node= qp_union; @@ -23017,6 +22479,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, test(select_lex->master_unit()->global_parameters->order_list.first); output->add_node(qp_union); +#endif } else if (!join->select_lex->master_unit()->derived || join->select_lex->master_unit()->derived->is_materialized_derived()) @@ -23555,16 +23018,21 @@ static void select_describe(JOIN *join, bool need_tmp_table, bool need_order, THD *thd=join->thd; select_result *result=join->result; DBUG_ENTER("select_describe"); -#if 0 - join->error= join->print_explain(result, thd->lex->describe, - FALSE, /* Not on-the-fly */ - need_tmp_table, need_order, distinct, - message); -#endif - //psergey-todo: save QPF here, too. + + // Update the QPF: + QPF_select *qp; + if ((qp= thd->lex->query_plan_footprint->get_select(join->select_lex->select_number))) + { + qp->using_temporary= need_tmp_table; + qp->using_filesort= need_order; + } + +/* + WE DONT NEED THIS here anymore: + join->save_qpf(thd->lex->query_plan_footprint, need_tmp_table, need_order, distinct, message); - +*/ for (SELECT_LEX_UNIT *unit= join->select_lex->first_inner_unit(); unit; unit= unit->next_unit()) diff --git a/sql/sql_union.cc b/sql/sql_union.cc index eb4454ecab3..b77b0669b50 100644 --- a/sql/sql_union.cc +++ b/sql/sql_union.cc @@ -626,6 +626,9 @@ bool st_select_lex_unit::exec() saved_error= optimize(); + + save_union_qpf(thd->lex->query_plan_footprint); + if (uncacheable || !item || !item->assigned() || describe) { for (SELECT_LEX *sl= select_cursor; sl; sl= sl->next_select()) @@ -772,6 +775,9 @@ bool st_select_lex_unit::exec() */ if (!fake_select_lex->ref_pointer_array) fake_select_lex->n_child_sum_items+= global_parameters->n_sum_items; + + + save_union_qpf_part2(thd->lex->query_plan_footprint); saved_error= mysql_select(thd, &fake_select_lex->ref_pointer_array, &result_table_list, -- cgit v1.2.1 From 8b7bbcf4dca77690091360e5ae7d011fb74554d6 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Thu, 27 Jun 2013 16:41:12 +0400 Subject: [SHOW] EXPLAIN UPDATE/DELETE, code re-structuring - Make query plan be re-saved after the first join execution (saving it after JOIN::cleanup is too late because EXPLAIN output is currently produced before that) - Handle QPF allocation/deallocation for edge cases, like unsuccessful BINLOG command. - Work around the problem with UNION's direct subselects not being visible. - Update test results ("Using temporary; Using filesort" are now always printed last in the Extra column) - This cset gets rid of memory leaks/crashes. Some result mismatches still remain. --- sql/log_event.cc | 1 + sql/opt_qpf.cc | 16 ++++++++++++---- sql/opt_qpf.h | 2 ++ sql/sql_lex.cc | 3 ++- sql/sql_parse.cc | 8 +++++++- sql/sql_select.cc | 38 +++++++++++++++++++++++++++++++++----- sql/sql_select.h | 3 +++ sql/sql_union.cc | 9 +++++---- 8 files changed, 65 insertions(+), 15 deletions(-) (limited to 'sql') diff --git a/sql/log_event.cc b/sql/log_event.cc index f4e34dd9224..a89806fa708 100644 --- a/sql/log_event.cc +++ b/sql/log_event.cc @@ -9041,6 +9041,7 @@ int Rows_log_event::do_apply_event(Relay_log_info const *rli) call might reset the value of current_stmt_binlog_format, so we need to do any changes to that value after this function. */ + delete_qpf_query(thd->lex); lex_start(thd); mysql_reset_thd_for_next_command(thd, 0); /* diff --git a/sql/opt_qpf.cc b/sql/opt_qpf.cc index 309e24471eb..37a01a4f832 100644 --- a/sql/opt_qpf.cc +++ b/sql/opt_qpf.cc @@ -13,6 +13,7 @@ QPF_query::QPF_query() { upd_del_plan= NULL; + operations= 0; //memset(&unions, 0, sizeof(unions)); //memset(&selects, 0, sizeof(selects)); } @@ -51,15 +52,18 @@ QPF_select *QPF_query::get_select(uint select_id) void QPF_query::add_node(QPF_node *node) { + operations++; if (node->get_type() == QPF_node::QPF_UNION) { QPF_union *u= (QPF_union*)node; uint select_id= u->get_select_id(); - DBUG_ASSERT(!get_union(select_id)); - if (unions.elements() <= select_id) unions.resize(max(select_id+1, unions.elements()*2), NULL); + QPF_union *old_node; + if ((old_node= get_union(select_id))) + delete old_node; + unions.at(select_id)= u; } else @@ -73,10 +77,14 @@ void QPF_query::add_node(QPF_node *node) else { uint select_id= sel->select_id; - DBUG_ASSERT(!get_select(select_id)); - + QPF_select *old_node; + //DBUG_ASSERT(!get_select(select_id)); if (selects.elements() <= select_id) selects.resize(max(select_id+1, selects.elements()*2), NULL); + + if ((old_node= get_select(select_id))) + delete old_node; + selects.at(select_id)= sel; } } diff --git a/sql/opt_qpf.h b/sql/opt_qpf.h index 1944f79254d..35afcde10df 100644 --- a/sql/opt_qpf.h +++ b/sql/opt_qpf.h @@ -223,6 +223,8 @@ private: Dynamic_array selects; //QPF_union *unions[MAX_TABLES]; //QPF_select *selects[MAX_TABLES]; + + longlong operations; }; diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc index c453a599dce..2e4eaf5b721 100644 --- a/sql/sql_lex.cc +++ b/sql/sql_lex.cc @@ -2552,7 +2552,8 @@ void Query_tables_list::destroy_query_tables_list() */ LEX::LEX() - :result(0), option_type(OPT_DEFAULT), is_lex_started(0), + : query_plan_footprint(NULL), + result(0), option_type(OPT_DEFAULT), is_lex_started(0), limit_rows_examined_cnt(ULONGLONG_MAX) { diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc index 6f2f7eaca20..9e477e62e19 100644 --- a/sql/sql_parse.cc +++ b/sql/sql_parse.cc @@ -4750,8 +4750,14 @@ finish: ha_maria::implicit_commit(thd, FALSE); #endif } - lex->unit.cleanup(); + //psergey-todo: print EXPLAIN here? After the above JOIN::cleanup calls? + // how do we print EXPLAIN extended, then? + if (lex->describe) + { + DBUG_ASSERT(lex->query_plan_footprint); + ///.. + } /* Free tables */ thd_proc_info(thd, "closing tables"); close_thread_tables(thd); diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 5e20d2faf24..5a5928f9b73 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -2347,6 +2347,36 @@ void JOIN::exec() exec_inner(); + if (!exec_qpf_saved) + { + if (select_lex->select_number != UINT_MAX && + select_lex->select_number != INT_MAX /* this is not a UNION's "fake select */ && + have_query_plan != QEP_NOT_PRESENT_YET && + have_query_plan != QEP_DELETED && // this happens when there was no QEP ever, but then + //cleanup() is called multiple times + + thd->lex->query_plan_footprint //&& // for "SET" command in SPs. + /*!thd->lex->query_plan_footprint->get_select(select_lex->select_number)*/) + { + const char *message= NULL; + + if (!table_count || !tables_list || zero_result_cause) + { + /* It's a degenerate join */ + message= zero_result_cause ? zero_result_cause : "No tables used"; + } + + save_qpf(thd->lex->query_plan_footprint, + need_tmp, // need_tmp_table + // !skip_sort_order && !no_order && + // (order || group_list), // bool need_order + order != 0 && !skip_sort_order, + select_distinct, // bool distinct + message); // message + } + exec_qpf_saved= true; + } + DBUG_EXECUTE_IF("show_explain_probe_join_exec_end", if (dbug_user_var_equals_int(thd, "show_explain_probe_select_id", @@ -11151,7 +11181,7 @@ void JOIN::cleanup(bool full) if (full) { - // + /* Save it again */ #if 0 if (select_lex->select_number != UINT_MAX && select_lex->select_number != INT_MAX /* this is not a UNION's "fake select */ && @@ -11159,8 +11189,8 @@ void JOIN::cleanup(bool full) have_query_plan != QEP_DELETED && // this happens when there was no QEP ever, but then //cleanup() is called multiple times - thd->lex->query_plan_footprint && // for "SET" command in SPs. - !thd->lex->query_plan_footprint->get_select(select_lex->select_number)) + thd->lex->query_plan_footprint //&& // for "SET" command in SPs. + /*!thd->lex->query_plan_footprint->get_select(select_lex->select_number)*/) { const char *message= NULL; @@ -11178,8 +11208,6 @@ void JOIN::cleanup(bool full) message); // message } #endif - // - have_query_plan= QEP_DELETED; //psergey: this is a problem! } diff --git a/sql/sql_select.h b/sql/sql_select.h index 6d4dfed479e..b394ee40276 100644 --- a/sql/sql_select.h +++ b/sql/sql_select.h @@ -1336,7 +1336,10 @@ public: pre_sort_join_tab= NULL; emb_sjm_nest= NULL; sjm_lookup_tables= 0; + + exec_qpf_saved= false; } + bool exec_qpf_saved; int prepare(Item ***rref_pointer_array, TABLE_LIST *tables, uint wind_num, COND *conds, uint og_num, ORDER *order, ORDER *group, diff --git a/sql/sql_union.cc b/sql/sql_union.cc index b77b0669b50..e4a9c7630e6 100644 --- a/sql/sql_union.cc +++ b/sql/sql_union.cc @@ -617,6 +617,7 @@ bool st_select_lex_unit::exec() ulonglong add_rows=0; ha_rows examined_rows= 0; DBUG_ENTER("st_select_lex_unit::exec"); + bool was_executed= executed; if (executed && !uncacheable && !describe) DBUG_RETURN(FALSE); @@ -626,8 +627,8 @@ bool st_select_lex_unit::exec() saved_error= optimize(); - - save_union_qpf(thd->lex->query_plan_footprint); + if (!was_executed && thd->lex->query_plan_footprint) + save_union_qpf(thd->lex->query_plan_footprint); if (uncacheable || !item || !item->assigned() || describe) { @@ -776,8 +777,8 @@ bool st_select_lex_unit::exec() if (!fake_select_lex->ref_pointer_array) fake_select_lex->n_child_sum_items+= global_parameters->n_sum_items; - - save_union_qpf_part2(thd->lex->query_plan_footprint); + if (!was_executed && thd->lex->query_plan_footprint) + save_union_qpf_part2(thd->lex->query_plan_footprint); saved_error= mysql_select(thd, &fake_select_lex->ref_pointer_array, &result_table_list, -- cgit v1.2.1 From d634638c5613683dd0690c1ed40db1bb75877e1c Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Thu, 27 Jun 2013 18:52:47 +0400 Subject: [SHOW] EXPLAIN UPDATE/DELETE, code re-structuring - If a subquery is correlated wrt a const table, it will change from being a "DEPENDENT SUBQUERY" into "SUBQUERY", at the end of its parent's JOIN::optimize() call. Handle this, update the subquery's QPF. - Make show_explain.test to work = "Query plan already deleted" does not happen anymore. = Handle special case of queries that don't have top-level selects, like SET x = (SELECT ...) --- sql/opt_qpf.h | 4 +++- sql/sql_lex.cc | 14 +++++++++++++- 2 files changed, 16 insertions(+), 2 deletions(-) (limited to 'sql') diff --git a/sql/opt_qpf.h b/sql/opt_qpf.h index 35afcde10df..2af04ab28a7 100644 --- a/sql/opt_qpf.h +++ b/sql/opt_qpf.h @@ -216,7 +216,9 @@ public: /* Produce a tabular EXPLAIN output */ int print_explain(select_result_sink *output, uint8 explain_flags); - + + /* If true, at least part of EXPLAIN can be printed */ + bool have_query_plan() { return upd_del_plan!= NULL || get_node(1) != NULL; } MEM_ROOT *mem_root; private: Dynamic_array unions; diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc index 2e4eaf5b721..f5aa84b6f41 100644 --- a/sql/sql_lex.cc +++ b/sql/sql_lex.cc @@ -3495,6 +3495,18 @@ bool st_select_lex::optimize_unflattened_subqueries(bool const_only) is_correlated_unit|= sl->is_correlated; inner_join->select_options= save_options; un->thd->lex->current_select= save_select; + /// psergey: + QPF_query *qpf; + if ((qpf= inner_join->thd->lex->query_plan_footprint)) + { + QPF_select *qp_sel; + if ((qp_sel= qpf->get_select(inner_join->select_lex->select_number))) + { + sl->set_explain_type(TRUE); + qp_sel->select_type= sl->type; + } + } + /// if (empty_union_result) { /* @@ -4182,7 +4194,7 @@ int LEX::print_explain(select_result_sink *output, uint8 explain_flags, bool *printed_anything) //TODO: remove printed_anything { int res; - if (query_plan_footprint) + if (query_plan_footprint && query_plan_footprint->have_query_plan()) { res= query_plan_footprint->print_explain(output, explain_flags); *printed_anything= true; -- cgit v1.2.1 From c0f7efb1aeeabebe502a786cc461a9d76bf18487 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Thu, 27 Jun 2013 16:28:57 +0400 Subject: Code cleanup --- sql/opt_qpf.cc | 1 - sql/sql_lex.cc | 101 +++++++----------------------------------------------- sql/sql_lex.h | 7 +--- sql/sql_select.cc | 40 ++++++++------------- sql/sql_update.cc | 1 - 5 files changed, 27 insertions(+), 123 deletions(-) (limited to 'sql') diff --git a/sql/opt_qpf.cc b/sql/opt_qpf.cc index 37a01a4f832..34b1a213207 100644 --- a/sql/opt_qpf.cc +++ b/sql/opt_qpf.cc @@ -339,7 +339,6 @@ int QPF_table_access::print_explain(select_result_sink *output, uint8 explain_fl push_str(&item_list, join_type_str[type]); /* `possible_keys` column */ - //push_str(item_list, "TODO"); if (possible_keys_str.length() > 0) push_string(&item_list, &possible_keys_str); else diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc index f5aa84b6f41..9337ed5c356 100644 --- a/sql/sql_lex.cc +++ b/sql/sql_lex.cc @@ -4191,7 +4191,7 @@ bool st_select_lex::is_merged_child_of(st_select_lex *ancestor) */ int LEX::print_explain(select_result_sink *output, uint8 explain_flags, - bool *printed_anything) //TODO: remove printed_anything + bool *printed_anything) { int res; if (query_plan_footprint && query_plan_footprint->have_query_plan()) @@ -4209,74 +4209,20 @@ int LEX::print_explain(select_result_sink *output, uint8 explain_flags, /* - -*/ -void st_select_lex::save_qpf(QPF_query *output) -{ - int res; - if (join && join->have_query_plan == JOIN::QEP_AVAILABLE) - { - /* - There is a number of reasons join can be marked as degenerate, so all - three conditions below can happen simultaneously, or individually: - */ - if (!join->table_count || !join->tables_list || join->zero_result_cause) - { - /* It's a degenerate join */ - const char *cause= join->zero_result_cause ? join-> zero_result_cause : - "No tables used"; - res= join->save_qpf(output, FALSE, FALSE, FALSE, cause); - } - else - { - join->save_qpf(output, join->need_tmp, // need_tmp_table - !join->skip_sort_order && !join->no_order && - (join->order || join->group_list), // bool need_order - join->select_distinct, // bool distinct - NULL); //const char *message - } - if (res) - goto err; + Save query plan of a UNION. The only variable member is whether the union has + "Using filesort". - for (SELECT_LEX_UNIT *unit= join->select_lex->first_inner_unit(); - unit; - unit= unit->next_unit()) - { - /* - Display subqueries only if they are not parts of eliminated WHERE/ON - clauses. - */ - if (!(unit->item && unit->item->eliminated)) - { - unit->save_qpf(output); - } - } - } - else - { - const char *msg; - if (!join) - DBUG_ASSERT(0); /* Seems not to be possible */ + There is also save_union_qpf_part2() function, which is called before we read + UNION's output. - /* Not printing anything useful, don't touch *printed_anything here */ - if (join->have_query_plan == JOIN::QEP_NOT_PRESENT_YET) - msg= "Not yet optimized"; - else - { - DBUG_ASSERT(join->have_query_plan == JOIN::QEP_DELETED); - msg= "Query plan already deleted"; - } - set_explain_type(TRUE/* on_the_fly */); - QPF_select *qp_sel= new (output->mem_root) QPF_select; - qp_sel->select_id= select_number; - qp_sel->select_type= type; - qp_sel->message= msg; - output->add_node(qp_sel); - } -err: - return ;//res; -} + The reason for it is examples like this: + SELECT col1 FROM t1 UNION SELECT col2 FROM t2 ORDER BY (select ... from t3 ...) + + Here, the (select ... from t3 ...) subquery must be a child of UNION's + st_select_lex. However, it is not connected as child until a very late + stage in execution. +*/ int st_select_lex_unit::save_union_qpf(QPF_query *output) { @@ -4307,11 +4253,7 @@ int st_select_lex_unit::save_union_qpf(QPF_query *output) } for (SELECT_LEX *sl= first; sl; sl= sl->next_select()) - { - if (!output->get_select(sl->select_number)) - sl->save_qpf(output); qpfu->add_select(sl->select_number); - } // Save the UNION node output->add_node(qpfu); @@ -4340,25 +4282,6 @@ int st_select_lex_unit::save_union_qpf_part2(QPF_query *output) } -int st_select_lex_unit::save_qpf(QPF_query *output) -{ - //int res= 0; - SELECT_LEX *first= first_select(); - - if (!first->next_select()) - { - /* This is a 1-way UNION, i.e. not really a UNION */ - if (!output->get_select(first->select_number)) - first->save_qpf(output); - return 0; - } - - save_union_qpf(output); - - return 0; -} - - /** A routine used by the parser to decide whether we are specifying a full partitioning or if only partitions to add or to split. diff --git a/sql/sql_lex.h b/sql/sql_lex.h index 77abc46d30b..4fe0e8b4d8b 100644 --- a/sql/sql_lex.h +++ b/sql/sql_lex.h @@ -732,7 +732,6 @@ public: List *get_unit_column_types(); - int save_qpf(QPF_query *output); int save_union_qpf(QPF_query *output); int save_union_qpf_part2(QPF_query *output); }; @@ -1053,11 +1052,7 @@ public: bool save_prep_leaf_tables(THD *thd); bool is_merged_child_of(st_select_lex *ancestor); -#if 0 - int print_explain(select_result_sink *output, uint8 explain_flags, - bool *printed_anything); -#endif - void save_qpf(QPF_query *output); + /* For MODE_ONLY_FULL_GROUP_BY we need to maintain two flags: - Non-aggregated fields are used in this select. diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 5a5928f9b73..201d1a6cc80 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -22464,7 +22464,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, const CHARSET_INFO *cs= system_charset_info; int quick_type; int error= 0; - DBUG_ENTER("JOIN::print_explain"); + DBUG_ENTER("JOIN::save_qpf"); DBUG_PRINT("info", ("Select 0x%lx, type %s, message %s", (ulong)join->select_lex, join->select_lex->type, message ? message : "NULL")); @@ -22920,14 +22920,6 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, if (table->reginfo.not_exists_optimize) qpt->push_extra(ET_NOT_EXISTS); - /* - if (quick_type == QUICK_SELECT_I::QS_TYPE_RANGE && - !(((QUICK_RANGE_SELECT*)(tab->select->quick))->mrr_flags & - HA_MRR_USE_DEFAULT_IMPL)) - { - extra.append(STRING_WITH_LEN("; Using MRR")); - } - */ if (quick_type == QUICK_SELECT_I::QS_TYPE_RANGE) { explain_append_mrr_info((QUICK_RANGE_SELECT*)(tab->select->quick), @@ -22940,13 +22932,11 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, { need_tmp_table=0; qp_sel->using_temporary= true; - ///extra.append(STRING_WITH_LEN("; Using temporary")); } if (need_order) { need_order=0; qp_sel->using_filesort= true; - ///extra.append(STRING_WITH_LEN("; Using filesort")); } if (distinct & test_all_bits(used_tables, join->select_list_used_tables)) @@ -22968,11 +22958,6 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, { qpt->push_extra(ET_FIRST_MATCH); TABLE *prev_table=tab->do_firstmatch->table; - /* - TODO: qpt->firstmatch_table... - This must be a reference to another QPF element. Or, its index. - */ - // extra.append(STRING_WITH_LEN("; FirstMatch(")); if (prev_table->derived_select_number) { char namebuf[NAME_LEN]; @@ -22984,7 +22969,6 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, } else qpt->firstmatch_table_name.append(prev_table->pos_in_table_list->alias); - //extra.append(STRING_WITH_LEN(")")); } } @@ -23033,11 +23017,21 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, DBUG_RETURN(error); } -////////////////////////////////////////////////////////////////////////////////////////////// - /* - See st_select_lex::print_explain() for the SHOW EXPLAIN counterpart + This function servers as "shortcut point" for EXPLAIN queries. + + For UNIONs and JOINs, EXPLAIN statement executes just like its SELECT + statement would execute, except that JOIN::exec() will call select_describe() + instead of actually executing the query. + + The purpose of select_describe() is: + - update the query plan with info about last-minute choices made at the start + of JOIN::exec + - Invoke "pseudo-execution" for the children subqueries. + + Overall, select_describe() is a legacy of old EXPLAIN implementation and + should be removed. */ static void select_describe(JOIN *join, bool need_tmp_table, bool need_order, @@ -23055,12 +23049,6 @@ static void select_describe(JOIN *join, bool need_tmp_table, bool need_order, qp->using_filesort= need_order; } -/* - WE DONT NEED THIS here anymore: - - join->save_qpf(thd->lex->query_plan_footprint, need_tmp_table, need_order, - distinct, message); -*/ for (SELECT_LEX_UNIT *unit= join->select_lex->first_inner_unit(); unit; unit= unit->next_unit()) diff --git a/sql/sql_update.cc b/sql/sql_update.cc index 96f49785a32..66a0a1eca21 100644 --- a/sql/sql_update.cc +++ b/sql/sql_update.cc @@ -1023,7 +1023,6 @@ exit_without_my_ok: List dummy; /* note: looked in 5.6 and they too use a dummy list like this */ result->prepare(dummy, &thd->lex->unit); thd->send_explain_fields(result); - //int err2= thd->lex->print_explain(result, 0 /* explain flags*/, &printed_anything); int err2= thd->lex->query_plan_footprint->print_explain(result, 0 /* explain flags*/); if (err2) -- cgit v1.2.1 From 5422098b758dfec801b32c833b8840ec96e00081 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Thu, 27 Jun 2013 17:02:44 +0400 Subject: More of code cleanup --- sql/opt_qpf.h | 54 +++++++++++++++++++++++++++++++----------------------- sql/sql_select.cc | 11 ++--------- 2 files changed, 33 insertions(+), 32 deletions(-) (limited to 'sql') diff --git a/sql/opt_qpf.h b/sql/opt_qpf.h index 2af04ab28a7..b82f004ff7f 100644 --- a/sql/opt_qpf.h +++ b/sql/opt_qpf.h @@ -50,18 +50,19 @@ class QPF_table_access; Query Plan Footprint of a SELECT. A select can be: - - a degenerate case. In this case, message!=NULL, and it contains a - description of what kind of degenerate case it is (e.g. "Impossible - WHERE"). - - a join. Here join_tabs has an array of JOIN_TAB query plan footprints. + 1. A degenerate case. In this case, message!=NULL, and it contains a + description of what kind of degenerate case it is (e.g. "Impossible + WHERE"). + 2. a non-degenrate join. In this case, join_tabs describes the join. In the non-degenerate case, a SELECT may have a GROUP BY/ORDER BY operation. - In both cases, a select may have children selects (see QPF_node) + + In both cases, the select may have children nodes. class QPF_node provides + a way get node's children. */ class QPF_select : public QPF_node { - /*Construction interface */ public: enum qpf_node_type get_type() { return QPF_SELECT; } @@ -107,10 +108,6 @@ public: bool using_temporary; bool using_filesort; - void print_tabular(select_result_sink *output, uint8 explain_flags//, - //bool *printed_anything - ); - int print_explain(QPF_query *query, select_result_sink *output, uint8 explain_flags); }; @@ -223,9 +220,13 @@ public: private: Dynamic_array unions; Dynamic_array selects; - //QPF_union *unions[MAX_TABLES]; - //QPF_select *selects[MAX_TABLES]; - + + /* + Debugging aid: count how many times add_node() was called. Ideally, it + should be one, we currently allow O(1) query plan saves for each + select or union. The goal is not to have O(#rows_in_some_table), which + is unacceptable. + */ longlong operations; }; @@ -303,9 +304,6 @@ public: uint key_no; uint key_length; - Dynamic_array extra_tags; - - //temporary: bool key_set; /* not set means 'NULL' should be printed */ StringBuffer<64> key; @@ -315,15 +313,18 @@ public: bool ref_set; /* not set means 'NULL' should be printed */ StringBuffer<64> ref; - bool rows_set; + bool rows_set; /* not set means 'NULL' should be printed */ ha_rows rows; - bool filtered_set; + bool filtered_set; /* not set means 'NULL' should be printed */ double filtered; - /* Various stuff for 'Extra' column*/ - uint join_cache_level; - + /* + Contents of the 'Extra' column. Some are converted into strings, some have + parameters, values for which are stored below. + */ + Dynamic_array extra_tags; + // Valid if ET_USING tag is present StringBuffer<64> quick_info; @@ -351,7 +352,10 @@ private: /* - Query Plan Footprint for an UPDATE statement + Query Plan Footprint for single-table UPDATE. + + This is similar to QPF_table_access, except that it is more restrictive. + Also, it can have UPDATE operation options, but currently there aren't any. */ class QPF_update : public QPF_node @@ -382,12 +386,16 @@ public: /* - Query Plan Footprint for a DELETE statement + Query Plan Footprint for a single-table DELETE. */ class QPF_delete: public QPF_update { public: + /* + TRUE means we're going to call handler->delete_all_rows() and not read any + rows. + */ bool deleting_all_rows; virtual enum qpf_node_type get_type() { return QPF_DELETE; } diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 201d1a6cc80..ed1cb35c29a 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -22448,9 +22448,9 @@ void append_possible_keys(String *str, TABLE *table, key_map possible_keys) /* Save Query Plan Footprint - push_extra - P + @note + Currently, this function may be called multiple times */ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, @@ -22471,11 +22471,6 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, DBUG_ASSERT(have_query_plan == QEP_AVAILABLE); /* Don't log this into the slow query log */ - - /* - NOTE: the number/types of items pushed into item_list must be in sync with - EXPLAIN column types as they're "defined" in THD::send_explain_fields() - */ if (message) { QPF_select *qp_sel; @@ -22998,8 +22993,6 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, output->add_node(qp_sel); } - //TODO: can a UNION have subquery children that are not union members? yes, - //perhaps... for (SELECT_LEX_UNIT *unit= join->select_lex->first_inner_unit(); unit; unit= unit->next_unit()) -- cgit v1.2.1 From befacafd73d4892f2ad84991ad7c2d4626e45c47 Mon Sep 17 00:00:00 2001 From: Sergey Petrunya Date: Thu, 27 Jun 2013 17:56:49 +0400 Subject: [SHOW] EXPLAIN UPDATE/DELETE, code re-structuring - Let Query Plan Footprint store join buffer type in binary form, not string. - Same for LooseScan type. --- sql/opt_qpf.cc | 15 +++++++++++++-- sql/opt_qpf.h | 14 ++++++++++++-- sql/opt_range.h | 6 +----- sql/sql_join_cache.cc | 35 +++++++++++++---------------------- sql/sql_join_cache.h | 7 ++++--- sql/sql_select.cc | 5 ++--- 6 files changed, 45 insertions(+), 37 deletions(-) (limited to 'sql') diff --git a/sql/opt_qpf.cc b/sql/opt_qpf.cc index 34b1a213207..6316fc0f0e9 100644 --- a/sql/opt_qpf.cc +++ b/sql/opt_qpf.cc @@ -489,7 +489,17 @@ void QPF_table_access::append_tag_name(String *str, enum Extra_tag tag) case ET_USING_JOIN_BUFFER: { str->append(extra_tag_text[tag]); - str->append(join_buffer_type); + + str->append(STRING_WITH_LEN(" (")); + const char *buffer_type= bka_type.incremental ? "incremental" : "flat"; + str->append(buffer_type); + str->append(STRING_WITH_LEN(", ")); + str->append(bka_type.join_alg); + str->append(STRING_WITH_LEN(" join")); + str->append(STRING_WITH_LEN(")")); + if (bka_type.mrr_type.length()) + str->append(bka_type.mrr_type); + break; } case ET_FIRST_MATCH: @@ -507,7 +517,8 @@ void QPF_table_access::append_tag_name(String *str, enum Extra_tag tag) case ET_USING_INDEX_FOR_GROUP_BY: { str->append(extra_tag_text[tag]); - str->append(loose_scan_type); + if (loose_scan_is_scanning) + str->append(" (scanning)"); break; } default: diff --git a/sql/opt_qpf.h b/sql/opt_qpf.h index b82f004ff7f..67f6b591e92 100644 --- a/sql/opt_qpf.h +++ b/sql/opt_qpf.h @@ -272,6 +272,15 @@ enum Extra_tag }; +typedef struct st_qpf_bka_type +{ + bool incremental; + const char *join_alg; + StringBuffer<64> mrr_type; + +} QPF_BKA_TYPE; + + /* Query Plan Footprint for a JOIN_TAB. */ @@ -329,7 +338,7 @@ public: StringBuffer<64> quick_info; // Valid if ET_USING_INDEX_FOR_GROUP_BY is present - StringBuffer<64> loose_scan_type; + bool loose_scan_is_scanning; // valid with ET_RANGE_CHECKED_FOR_EACH_RECORD key_map range_checked_map; @@ -338,7 +347,8 @@ public: StringBuffer<64> mrr_type; // valid with ET_USING_JOIN_BUFFER - StringBuffer<64> join_buffer_type; + //StringBuffer<64> join_buffer_type; + QPF_BKA_TYPE bka_type; //TABLE *firstmatch_table; StringBuffer<64> firstmatch_table_name; diff --git a/sql/opt_range.h b/sql/opt_range.h index ddaa5c5e59a..e67274c19a6 100644 --- a/sql/opt_range.h +++ b/sql/opt_range.h @@ -944,11 +944,7 @@ public: void dbug_dump(int indent, bool verbose); #endif bool is_agg_distinct() { return have_agg_distinct; } - virtual void append_loose_scan_type(String *str) - { - if (is_index_scan) - str->append(STRING_WITH_LEN(" (scanning)")); - } + bool loose_scan_is_scanning() { return is_index_scan; } }; diff --git a/sql/sql_join_cache.cc b/sql/sql_join_cache.cc index 9fca8730cb5..7710db5c7ba 100644 --- a/sql/sql_join_cache.cc +++ b/sql/sql_join_cache.cc @@ -2568,34 +2568,26 @@ finish: none */ -void JOIN_CACHE::print_explain_comment(String *str) +void JOIN_CACHE::save_qpf(struct st_qpf_bka_type *qpf) { - str->append(STRING_WITH_LEN(" (")); - const char *buffer_type= prev_cache ? "incremental" : "flat"; - str->append(buffer_type); - str->append(STRING_WITH_LEN(", ")); - - const char *join_alg=""; + qpf->incremental= test(prev_cache); + switch (get_join_alg()) { case BNL_JOIN_ALG: - join_alg= "BNL"; + qpf->join_alg= "BNL"; break; case BNLH_JOIN_ALG: - join_alg= "BNLH"; + qpf->join_alg= "BNLH"; break; case BKA_JOIN_ALG: - join_alg= "BKA"; + qpf->join_alg= "BKA"; break; case BKAH_JOIN_ALG: - join_alg= "BKAH"; + qpf->join_alg= "BKAH"; break; default: DBUG_ASSERT(0); } - - str->append(join_alg); - str->append(STRING_WITH_LEN(" join")); - str->append(STRING_WITH_LEN(")")); } /** @@ -2621,18 +2613,17 @@ static void add_mrr_explain_info(String *str, uint mrr_mode, handler *file) } } - -void JOIN_CACHE_BKA::print_explain_comment(String *str) +void JOIN_CACHE_BKA::save_qpf(struct st_qpf_bka_type *qpf) { - JOIN_CACHE::print_explain_comment(str); - add_mrr_explain_info(str, mrr_mode, join_tab->table->file); + JOIN_CACHE::save_qpf(qpf); + add_mrr_explain_info(&qpf->mrr_type, mrr_mode, join_tab->table->file); } -void JOIN_CACHE_BKAH::print_explain_comment(String *str) +void JOIN_CACHE_BKAH::save_qpf(struct st_qpf_bka_type *qpf) { - JOIN_CACHE::print_explain_comment(str); - add_mrr_explain_info(str, mrr_mode, join_tab->table->file); + JOIN_CACHE::save_qpf(qpf); + add_mrr_explain_info(&qpf->mrr_type, mrr_mode, join_tab->table->file); } diff --git a/sql/sql_join_cache.h b/sql/sql_join_cache.h index 6953f6881ee..75589c3395f 100644 --- a/sql/sql_join_cache.h +++ b/sql/sql_join_cache.h @@ -63,6 +63,7 @@ typedef struct st_cache_field { class JOIN_TAB_SCAN; +struct st_qpf_bka_type; /* JOIN_CACHE is the base class to support the implementations of @@ -657,7 +658,7 @@ public: enum_nested_loop_state join_records(bool skip_last); /* Add a comment on the join algorithm employed by the join cache */ - virtual void print_explain_comment(String *str); + virtual void save_qpf(struct st_qpf_bka_type *qpf); THD *thd(); @@ -1335,7 +1336,7 @@ public: /* Check index condition of the joined table for a record from BKA cache */ bool skip_index_tuple(range_id_t range_info); - void print_explain_comment(String *str); + void save_qpf(struct st_qpf_bka_type *qpf); }; @@ -1426,5 +1427,5 @@ public: /* Check index condition of the joined table for a record from BKAH cache */ bool skip_index_tuple(range_id_t range_info); - void print_explain_comment(String *str); + void save_qpf(struct st_qpf_bka_type *qpf); }; diff --git a/sql/sql_select.cc b/sql/sql_select.cc index ed1cb35c29a..763c719f250 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -22907,7 +22907,7 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, QUICK_GROUP_MIN_MAX_SELECT *qgs= (QUICK_GROUP_MIN_MAX_SELECT *) tab->select->quick; qpt->push_extra(ET_USING_INDEX_FOR_GROUP_BY); - qgs->append_loose_scan_type(&qpt->loose_scan_type); + qpt->loose_scan_is_scanning= qgs->loose_scan_is_scanning(); } else qpt->push_extra(ET_USING_INDEX); @@ -22979,9 +22979,8 @@ int JOIN::save_qpf(QPF_query *output, bool need_tmp_table, bool need_order, if (tab->cache) { qpt->push_extra(ET_USING_JOIN_BUFFER); - tab->cache->print_explain_comment(&qpt->join_buffer_type); + tab->cache->save_qpf(&qpt->bka_type); } - } if (saved_join_tab) -- cgit v1.2.1