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Merge ibabaev@bk-internal.mysql.com:/home/bk/mysql-4.1

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into rurik.mysql.com:/home/igor/mysql-4.1
This commit is contained in:
igor@rurik.mysql.com
2004-08-20 16:32:40 -07:00
parent b817b007f9 75454b0a1d
commit 02f9e068b9
17 changed files with 316 additions and 260 deletions
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44
sql/sql_select.cc
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@ -4379,25 +4379,39 @@ COND *eliminate_not_funcs(THD *thd, COND *cond)
static COND *
optimize_cond(THD *thd, COND *conds, Item::cond_result *cond_value)
{
SELECT_LEX *select= thd->lex->current_select;
DBUG_ENTER("optimize_cond");
if (!conds)
if (conds)
{
DBUG_EXECUTE("where", print_where(conds, "original"););
/* Eliminate NOT operators; in case of PS/SP do it once */
if (thd->current_arena->is_first_stmt_execute())
{
Item_arena *arena= thd->current_arena, backup;
thd->set_n_backup_item_arena(arena, &backup);
conds= eliminate_not_funcs(thd, conds);
select->prep_where= conds->copy_andor_structure(thd);
thd->restore_backup_item_arena(arena, &backup);
}
else
conds= eliminate_not_funcs(thd, conds);
DBUG_EXECUTE("where", print_where(conds, "after negation elimination"););
/* change field = field to field = const for each found field = const */
propagate_cond_constants((I_List<COND_CMP> *) 0, conds, conds);
/*
Remove all instances of item == item
Remove all and-levels where CONST item != CONST item
*/
DBUG_EXECUTE("where", print_where(conds, "after const change"););
conds= remove_eq_conds(thd, conds, cond_value);
DBUG_EXECUTE("info", print_where(conds, "after remove"););
}
else
{
*cond_value= Item::COND_TRUE;
DBUG_RETURN(conds);
select->prep_where= 0;
}
DBUG_EXECUTE("where",print_where(conds,"original"););
/* eliminate NOT operators */
conds= eliminate_not_funcs(thd, conds);
DBUG_EXECUTE("where", print_where(conds, "after negation elimination"););
/* change field = field to field = const for each found field = const */
propagate_cond_constants((I_List<COND_CMP> *) 0,conds,conds);
/*
Remove all instances of item == item
Remove all and-levels where CONST item != CONST item
*/
DBUG_EXECUTE("where",print_where(conds,"after const change"););
conds= remove_eq_conds(thd, conds, cond_value) ;
DBUG_EXECUTE("info",print_where(conds,"after remove"););
DBUG_RETURN(conds);
}