diff options
Diffstat (limited to 'sql')
| -rw-r--r-- | sql/sql_select.cc | 4 | ||||
| -rw-r--r-- | sql/sql_select.h | 1 | ||||
| -rw-r--r-- | sql/sql_update.cc | 16 |
3 files changed, 14 insertions, 7 deletions
diff --git a/sql/sql_select.cc b/sql/sql_select.cc index f057e30b6eb..5ef3f4d9fda 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -69,8 +69,6 @@ static int return_zero_rows(JOIN *join, select_result *res,TABLE_LIST *tables, SELECT_LEX_UNIT *unit); static COND *optimize_cond(THD *thd, COND *conds, Item::cond_result *cond_value); -static COND *remove_eq_conds(THD *thd, COND *cond, - Item::cond_result *cond_value); static bool const_expression_in_where(COND *conds,Item *item, Item **comp_item); static bool open_tmp_table(TABLE *table); static bool create_myisam_tmp_table(TABLE *table,TMP_TABLE_PARAM *param, @@ -4615,7 +4613,7 @@ optimize_cond(THD *thd, COND *conds, Item::cond_result *cond_value) COND_FALSE always false ( 1 = 2 ) */ -static COND * +COND * remove_eq_conds(THD *thd, COND *cond, Item::cond_result *cond_value) { if (cond->type() == Item::COND_ITEM) diff --git a/sql/sql_select.h b/sql/sql_select.h index fe9bb7d69d3..636ee967645 100644 --- a/sql/sql_select.h +++ b/sql/sql_select.h @@ -457,3 +457,4 @@ bool cp_buffer_from_ref(THD *thd, TABLE_REF *ref); bool error_if_full_join(JOIN *join); int report_error(TABLE *table, int error); int safe_index_read(JOIN_TAB *tab); +COND *remove_eq_conds(THD *thd, COND *cond, Item::cond_result *cond_value); diff --git a/sql/sql_update.cc b/sql/sql_update.cc index b6bce800b0e..cb8064bef87 100644 --- a/sql/sql_update.cc +++ b/sql/sql_update.cc @@ -70,7 +70,7 @@ int mysql_update(THD *thd, ha_rows updated, found; key_map old_used_keys; TABLE *table; - SQL_SELECT *select; + SQL_SELECT *select= 0; READ_RECORD info; TABLE_LIST *update_table_list= ((TABLE_LIST*) thd->lex->select_lex.table_list.first); @@ -131,11 +131,19 @@ int mysql_update(THD *thd, DBUG_RETURN(-1); /* purecov: inspected */ } + if (conds) + { + Item::cond_result cond_value; + conds= remove_eq_conds(thd, conds, &cond_value); + if (cond_value == Item::COND_FALSE) + limit= 0; // Impossible WHERE + } // Don't count on usage of 'only index' when calculating which key to use table->used_keys.clear_all(); - select=make_select(table,0,0,conds,&error); - if (error || - (select && select->check_quick(thd, safe_update, limit)) || !limit) + if (limit) + select=make_select(table,0,0,conds,&error); + if (error || !limit || + (select && select->check_quick(thd, safe_update, limit))) { delete select; free_underlaid_joins(thd, &thd->lex->select_lex); |