diff options
Diffstat (limited to 'sql/item.cc')
| -rw-r--r-- | sql/item.cc | 34 |
1 files changed, 31 insertions, 3 deletions
diff --git a/sql/item.cc b/sql/item.cc index 636cefb511b..bdf180b4828 100644 --- a/sql/item.cc +++ b/sql/item.cc @@ -117,7 +117,9 @@ void Item::set_name(const char *str, uint length, CHARSET_INFO *cs) /* - This function is only called when comparing items in the WHERE clause + This function is called when: + - Comparing items in the WHERE clause (when doing where optimization) + - When trying to find an ORDER BY/GROUP BY item in the SELECT part */ bool Item::eq(const Item *item, bool binary_cmp) const @@ -243,6 +245,7 @@ void Item_field::set_field(Field *field_par) decimals= field->decimals(); table_name=field_par->table_name; field_name=field_par->field_name; + db_name=field_par->table->table_cache_key; unsigned_flag=test(field_par->flags & UNSIGNED_FLAG); set_charset(field_par->charset(), COER_IMPLICIT); } @@ -344,9 +347,34 @@ longlong Item_field::val_int_result() return result_field->val_int(); } + bool Item_field::eq(const Item *item, bool binary_cmp) const { - return item->type() == FIELD_ITEM && ((Item_field*) item)->field == field; + if (item->type() != FIELD_ITEM) + return 0; + + Item_field *item_field= (Item_field*) item; + if (item_field->field) + return item_field->field == field; + /* + We may come here when we are trying to find a function in a GROUP BY + clause from the select list. + In this case the '100 % correct' way to do this would be to first + run fix_fields() on the GROUP BY item and then retry this function, but + I think it's better to relax the checking a bit as we will in + most cases do the correct thing by just checking the field name. + (In cases where we would choose wrong we would have to generate a + ER_NON_UNIQ_ERROR). + */ + return (!my_strcasecmp(system_charset_info, item_field->name, + field_name) && + (!item_field->table_name || + (!my_strcasecmp(table_alias_charset, item_field->table_name, + table_name) && + (!item_field->db_name || + (item_field->db_name && !my_strcasecmp(table_alias_charset, + item_field->db_name, + db_name)))))); } table_map Item_field::used_tables() const @@ -837,7 +865,7 @@ bool Item_field::fix_fields(THD *thd, TABLE_LIST *tables, Item **ref) return rf->fix_fields(thd, tables, ref) || rf->check_cols(1); } } - } + } else if (!tmp) return -1; |