diff options
Diffstat (limited to 'sql')
| -rw-r--r-- | sql/field.cc | 76 | ||||
| -rw-r--r-- | sql/field.h | 15 | ||||
| -rw-r--r-- | sql/item.cc | 2 | ||||
| -rw-r--r-- | sql/item_cmpfunc.cc | 2 | ||||
| -rw-r--r-- | sql/sql_select.cc | 4 | ||||
| -rw-r--r-- | sql/sql_statistics.cc | 3 |
6 files changed, 45 insertions, 57 deletions
diff --git a/sql/field.cc b/sql/field.cc index 5e4d29045a3..51938bab9b3 100644 --- a/sql/field.cc +++ b/sql/field.cc @@ -11369,7 +11369,7 @@ void Field::print_key_value_binary(String *out, const uchar* key, uint32 length) If the column is the first component of a key, then statistics for the column are available from the range optimizer. Sets the bit in Field::stats_table - a) NDV is available + a) Number of distinct values(NDV) is available b) Statistics are available for the non-const argument of a range predicate */ @@ -11381,15 +11381,12 @@ void Field::statistics_available_via_keys() while ((key= it++) != key_map::Iterator::BITMAP_END) { KEY *keyinfo= table->key_info + key; - if (keyinfo->usable_key_parts == 1 && - field_index + 1 == keyinfo->key_part->fieldnr) + DBUG_ASSERT(field_index + 1 == keyinfo->key_part->fieldnr); + stats_available|= (1 << STATISTICS_FOR_RANGE_PREDICATES_AVAILABLE); + if (keyinfo->actual_rec_per_key(0)) { - stats_available|= (1 << STATISTICS_FOR_RANGE_PREDICATES_AVAILABLE); - if (keyinfo->actual_rec_per_key(0)) - { - stats_available|= (1 << STATISTICS_FOR_NDV_AVAILABLE); - return; - } + stats_available|= (1 << STATISTICS_FOR_NDV_AVAILABLE); + return; } } } @@ -11402,11 +11399,12 @@ void Field::statistics_available_via_keys() void Field::statistics_available_via_stat_tables() { - if (!(read_stats && !read_stats->no_stat_values_provided())) - return; - stats_available|= (1 << STATISTICS_FOR_RANGE_PREDICATES_AVAILABLE); - if (!read_stats->is_null(COLUMN_STAT_AVG_FREQUENCY)) - stats_available|= (1 << STATISTICS_FOR_NDV_AVAILABLE); + if (read_stats && !read_stats->no_stat_values_provided()) + { + stats_available|= (1 << STATISTICS_FOR_RANGE_PREDICATES_AVAILABLE); + if (!read_stats->is_null(COLUMN_STAT_AVG_FREQUENCY)) + stats_available|= (1 << STATISTICS_FOR_NDV_AVAILABLE); + } } @@ -11414,14 +11412,19 @@ void Field::statistics_available_via_stat_tables() @brief Check if statistics for a column are available via indexes or stat tables + @details + This function checks if there are statistics for a column via indexes + or stat tables. Also if the member Field::stats_available + has not been updated then update it + @retval TRUE : statistics available for the column FALSE : OTHERWISE */ -bool Field::is_statistics_available() +bool Field::is_range_statistics_available() { - if (!(stats_available & (1 << STATISTICS_CACHED))) + if (!stats_available) { statistics_available_via_keys(); statistics_available_via_stat_tables(); @@ -11433,7 +11436,8 @@ bool Field::is_statistics_available() /* @brief - Check if ndv for a column are available via indexes or stat tables + Check if number of distinct values (NDV) for a column are available + via indexes or stat tables @retval TRUE : ndv available for the column @@ -11442,12 +11446,11 @@ bool Field::is_statistics_available() bool Field::is_ndv_available() { - if (!(stats_available & (1 << STATISTICS_CACHED))) + if (!stats_available) { - bool res= is_ndv_available_via_keys() || - is_ndv_available_via_stat_tables(); stats_available|= (1 << STATISTICS_CACHED); - return res; + return is_ndv_available_via_keys() || + is_ndv_available_via_stat_tables(); } return (stats_available & (1 << STATISTICS_FOR_NDV_AVAILABLE)); } @@ -11469,7 +11472,7 @@ bool Field::is_ndv_available_via_keys() while ((key= it++) != key_map::Iterator::BITMAP_END) { KEY *keyinfo= table->key_info + key; - if (is_first_component_of_key(keyinfo) && keyinfo->actual_rec_per_key(0)) + if (keyinfo->actual_rec_per_key(0)) { stats_available|= (1 << STATISTICS_FOR_NDV_AVAILABLE); return true; @@ -11490,30 +11493,13 @@ bool Field::is_ndv_available_via_keys() bool Field::is_ndv_available_via_stat_tables() { - if (!(read_stats && !read_stats->no_stat_values_provided() && + if ((read_stats && !read_stats->no_stat_values_provided() && !read_stats->is_null(COLUMN_STAT_AVG_FREQUENCY))) - return false; - stats_available|= (1 << STATISTICS_FOR_NDV_AVAILABLE); - return true; -} - - -/* - @brief - Checks if a field is the first component of a given key - - @param - key given key - - @retval - TRUE : field is the first component of the given key - FALSE : otherwise -*/ - -bool Field::is_first_component_of_key(KEY *key) -{ - DBUG_ASSERT(key->usable_key_parts >= 1); - return field_index + 1 == key->key_part->fieldnr; + { + stats_available|= (1 << STATISTICS_FOR_NDV_AVAILABLE); + return true; + } + return false; } diff --git a/sql/field.h b/sql/field.h index e4a1e2b12c4..18633f8f1fe 100644 --- a/sql/field.h +++ b/sql/field.h @@ -832,6 +832,13 @@ public: uint32 flags; uint16 field_index; // field number in fields array uchar null_bit; // Bit used to test null bit + + /* + Caches the value of whether statistics are available for a field + This is reset for each query in THD::init() + */ + uint8 stats_available; + /** If true, this field was created in create_tmp_field_from_item from a NULL value. This means that the type of the field is just a guess, and the type @@ -876,11 +883,6 @@ public: STATISTICS_FOR_NDV_AVAILABLE }; - /* - Caches the value of whether statistics are available for a field or not. - */ - uint stats_available; - /* This is additional data provided for any computed(virtual) field, default function or check constraint. @@ -1919,10 +1921,9 @@ public: /* Mark field in read map. Updates also virtual fields */ void register_field_in_read_map(); - bool is_first_component_of_key(KEY *key); void statistics_available_via_keys(); void statistics_available_via_stat_tables(); - bool is_statistics_available(); + bool is_range_statistics_available(); bool is_ndv_available(); bool is_ndv_available_via_stat_tables(); bool is_ndv_available_via_keys(); diff --git a/sql/item.cc b/sql/item.cc index c72f488c81d..71b73ae314f 100644 --- a/sql/item.cc +++ b/sql/item.cc @@ -9367,7 +9367,7 @@ bool Item_field::predicate_selectivity_checker(void *arg) { same_field_arg->item= this; same_field_arg->is_stats_available= - field->is_statistics_available() || + field->is_range_statistics_available() || (item_equal && item_equal->is_statistics_available()); return false; } diff --git a/sql/item_cmpfunc.cc b/sql/item_cmpfunc.cc index 711f1b939a9..4fe1d78af45 100644 --- a/sql/item_cmpfunc.cc +++ b/sql/item_cmpfunc.cc @@ -7244,7 +7244,7 @@ bool Item_equal::is_statistics_available() while (it++) { Field *field= it.get_curr_field(); - if (field->is_statistics_available()) + if (field->is_range_statistics_available()) return true; } return false; diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 3553ee78c5b..c04eda05c57 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -29478,6 +29478,10 @@ void unpack_to_base_table_fields(TABLE *table) bool is_range_predicate(Item *item, Item *value) { + /* + calling real_item() here so that if the item is a REF_ITEM + then we would get the item field it is referring to + */ Item *field= item->real_item(); if (field->type() == Item::FIELD_ITEM && !field->const_item() && (!value || !value->is_expensive())) diff --git a/sql/sql_statistics.cc b/sql/sql_statistics.cc index 71d472feaba..5a93df13cf8 100644 --- a/sql/sql_statistics.cc +++ b/sql/sql_statistics.cc @@ -3158,10 +3158,7 @@ static void dump_stats_from_share_to_table(TABLE *table) Field **field_ptr= table_share->field; Field **table_field_ptr= table->field; for ( ; *field_ptr; field_ptr++, table_field_ptr++) - { (*table_field_ptr)->read_stats= (*field_ptr)->read_stats; - (*table_field_ptr)->stats_available= (*field_ptr)->stats_available; - } table->stats_is_read= true; } |