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removing additional IN subquery condition

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fixed IN optimisation bug


mysql-test/r/subselect.result:
  test of IN optimisation bug
mysql-test/t/subselect.test:
  test of IN optimisation bug
sql/item_subselect.cc:
  fixed IN optimisation bug
sql/mysql_priv.h:
  constant for additional IN subquery condition detecting
sql/mysqld.cc:
  constant for additional IN subquery condition detecting
sql/sql_select.cc:
  removing additional IN subquery condition
This commit is contained in:
unknown
2003-09-08 21:58:09 +03:00
parent b036ffec6c
commit d17cfa9caa
6 changed files with 97 additions and 14 deletions
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46
sql/sql_select.cc
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@ -160,6 +160,7 @@ static bool init_sum_functions(Item_sum **func, Item_sum **end);
static bool update_sum_func(Item_sum **func);
static void select_describe(JOIN *join, bool need_tmp_table, bool need_order,
bool distinct, const char *message=NullS);
static Item *remove_additional_cond(Item* conds);
/*
@ -464,8 +465,10 @@ bool JOIN::test_in_subselect(Item **where)
((class Item_func *)this->conds)->functype() ==
Item_func::COND_AND_FUNC)
{
*where= conds;
join_tab->info= "Using index; Using where";
if ((*where= remove_additional_cond(conds)))
join_tab->info= "Using index; Using where";
else
join_tab->info= "Using index";
return 1;
}
return 0;
@ -806,6 +809,12 @@ JOIN::optimize()
{
join_tab[0].type= JT_INDEX_IN;
error= 0;
if ((conds= remove_additional_cond(conds)))
join_tab->info= "Using index; Using where";
else
join_tab->info= "Using index";
DBUG_RETURN(unit->item->
change_engine(new subselect_indexin_engine(thd,
join_tab,
@ -3990,6 +3999,39 @@ change_cond_ref_to_const(I_List<COND_CMP> *save_list,Item *and_father,
}
}
/*
Remove additional condition inserted by IN/ALL/ANY transformation
SYNOPSIS
remove_additional_cond()
conds - condition for processing
RETURN VALUES
new conditions
*/
static Item *remove_additional_cond(Item* conds)
{
if (conds->name == in_additional_cond)
return 0;
if (conds->type() == Item::COND_ITEM)
{
Item_cond *cnd= (Item_cond*) conds;
List_iterator<Item> li(*(cnd->argument_list()));
Item *item;
while ((item= li++))
{
if (item->name == in_additional_cond)
{
li.remove();
if (cnd->argument_list()->elements == 1)
return cnd->argument_list()->head();
return conds;
}
}
}
return conds;
}
static void
propagate_cond_constants(I_List<COND_CMP> *save_list,COND *and_level,