diff options
Diffstat (limited to 'sql/item_sum.h')
| -rw-r--r-- | sql/item_sum.h | 85 |
1 files changed, 34 insertions, 51 deletions
diff --git a/sql/item_sum.h b/sql/item_sum.h index 1c31f1a9b70..cac080c5807 100644 --- a/sql/item_sum.h +++ b/sql/item_sum.h @@ -204,18 +204,24 @@ class Item_sum_count_distinct :public Item_sum_int uint key_length; CHARSET_INFO *key_charset; - // calculated based on max_heap_table_size. If reached, - // walk the tree and dump it into MyISAM table + /* + Calculated based on max_heap_table_size. If reached, + walk the tree and dump it into MyISAM table + */ uint max_elements_in_tree; - // the first few bytes of record ( at least one) - // are just markers for deleted and NULLs. We want to skip them since - // they will just bloat the tree without providing any valuable info + /* + The first few bytes of record ( at least one) + are just markers for deleted and NULLs. We want to skip them since + they will just bloat the tree without providing any valuable info + */ int rec_offset; - // If there are no blobs, we can use a tree, which - // is faster than heap table. In that case, we still use the table - // to help get things set up, but we insert nothing in it + /* + If there are no blobs, we can use a tree, which + is faster than heap table. In that case, we still use the table + to help get things set up, but we insert nothing in it + */ bool use_tree; bool always_null; // Set to 1 if the result is always NULL @@ -236,7 +242,8 @@ class Item_sum_count_distinct :public Item_sum_int Item_sum_count_distinct(THD *thd, Item_sum_count_distinct *item) :Item_sum_int(thd, item), table(item->table), used_table_cache(item->used_table_cache), - field_lengths(item->field_lengths), tmp_table_param(item->tmp_table_param), + field_lengths(item->field_lengths), + tmp_table_param(item->tmp_table_param), tree(item->tree), original(item), key_length(item->key_length), max_elements_in_tree(item->max_elements_in_tree), rec_offset(item->rec_offset), use_tree(item->use_tree), @@ -318,18 +325,17 @@ public: void fix_length_and_dec() {} }; -/* - -variance(a) = - -= sum (ai - avg(a))^2 / count(a) ) -= sum (ai^2 - 2*ai*avg(a) + avg(a)^2) / count(a) -= (sum(ai^2) - sum(2*ai*avg(a)) + sum(avg(a)^2))/count(a) = -= (sum(ai^2) - 2*avg(a)*sum(a) + count(a)*avg(a)^2)/count(a) = -= (sum(ai^2) - 2*sum(a)*sum(a)/count(a) + count(a)*sum(a)^2/count(a)^2 )/count(a) = -= (sum(ai^2) - 2*sum(a)^2/count(a) + sum(a)^2/count(a) )/count(a) = -= (sum(ai^2) - sum(a)^2/count(a))/count(a) +/* + variance(a) = + + = sum (ai - avg(a))^2 / count(a) ) + = sum (ai^2 - 2*ai*avg(a) + avg(a)^2) / count(a) + = (sum(ai^2) - sum(2*ai*avg(a)) + sum(avg(a)^2))/count(a) = + = (sum(ai^2) - 2*avg(a)*sum(a) + count(a)*avg(a)^2)/count(a) = + = (sum(ai^2) - 2*sum(a)*sum(a)/count(a) + count(a)*sum(a)^2/count(a)^2 )/count(a) = + = (sum(ai^2) - 2*sum(a)^2/count(a) + sum(a)^2/count(a) )/count(a) = + = (sum(ai^2) - sum(a)^2/count(a))/count(a) */ class Item_sum_variance : public Item_sum_num @@ -515,8 +521,9 @@ class Item_sum_xor :public Item_sum_bit /* -** user defined aggregates + User defined aggregates */ + #ifdef HAVE_DLOPEN class Item_udf_sum : public Item_sum @@ -682,12 +689,13 @@ class Item_func_group_concat : public Item_sum friend int group_concat_key_cmp_with_distinct(void* arg, byte* key1, byte* key2); - friend int group_concat_key_cmp_with_order(void* arg, byte* key1, byte* key2); + friend int group_concat_key_cmp_with_order(void* arg, byte* key1, + byte* key2); friend int group_concat_key_cmp_with_distinct_and_order(void* arg, byte* key1, byte* key2); friend int dump_leaf_key(byte* key, uint32 count __attribute__((unused)), - Item_func_group_concat *group_concat_item); + Item_func_group_concat *group_concat_item); public: String result; @@ -696,12 +704,13 @@ class Item_func_group_concat : public Item_sum TREE *tree; TABLE *table; ORDER **order; + uint *field_offsets; TABLE_LIST *tables_list; ulong group_concat_max_len; uint show_elements; uint arg_count_order; uint arg_count_field; - uint arg_show_fields; + uint field_list_offset; uint count_cut_values; /* Following is 0 normal object and pointer to original one for copy @@ -712,38 +721,12 @@ class Item_func_group_concat : public Item_sum Item_func_group_concat(bool is_distinct,List<Item> *is_select, SQL_LIST *is_order,String *is_separator); - Item_func_group_concat(THD *thd, Item_func_group_concat *item) - :Item_sum(thd, item),item_thd(thd), - tmp_table_param(item->tmp_table_param), - max_elements_in_tree(item->max_elements_in_tree), - warning(item->warning), - warning_available(item->warning_available), - key_length(item->key_length), - rec_offset(item->rec_offset), - tree_mode(item->tree_mode), - distinct(item->distinct), - warning_for_row(item->warning_for_row), - separator(item->separator), - tree(item->tree), - table(item->table), - order(item->order), - tables_list(item->tables_list), - group_concat_max_len(item->group_concat_max_len), - show_elements(item->show_elements), - arg_count_order(item->arg_count_order), - arg_count_field(item->arg_count_field), - arg_show_fields(item->arg_show_fields), - count_cut_values(item->count_cut_values), - original(item) - { - quick_group= item->quick_group; - }; + Item_func_group_concat(THD *thd, Item_func_group_concat *item); ~Item_func_group_concat(); void cleanup(); enum Sumfunctype sum_func () const {return GROUP_CONCAT_FUNC;} const char *func_name() const { return "group_concat"; } - enum Type type() const { return SUM_FUNC_ITEM; } virtual Item_result result_type () const { return STRING_RESULT; } void clear(); bool add(); |