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MDEV-4836: Merge into 5.5-main

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This commit is contained in:
Sergey Petrunya
2013-09-03 18:41:07 +04:00
parent de1c060ecf d6f7649d3c
commit 92003f0166
6 changed files with 193 additions and 58 deletions
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125
sql/sql_select.cc
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@@ -13536,6 +13536,57 @@ void propagate_new_equalities(THD *thd, Item *cond,
}
}
/*
Check if cond_is_datetime_is_null() is true for the condition cond, or
for any of its AND/OR-children
*/
bool cond_has_datetime_is_null(Item *cond)
{
if (cond_is_datetime_is_null(cond))
return true;
if (cond->type() == Item::COND_ITEM)
{
List<Item> *cond_arg_list= ((Item_cond*) cond)->argument_list();
List_iterator<Item> li(*cond_arg_list);
Item *item;
while ((item= li++))
{
if (cond_has_datetime_is_null(item))
return true;
}
}
return false;
}
/*
Check if passed condtition has for of
not_null_date_col IS NULL
where not_null_date_col has a datte or datetime type
*/
bool cond_is_datetime_is_null(Item *cond)
{
if (cond->type() == Item::FUNC_ITEM &&
((Item_func*) cond)->functype() == Item_func::ISNULL_FUNC)
{
Item **args= ((Item_func_isnull*) cond)->arguments();
if (args[0]->type() == Item::FIELD_ITEM)
{
Field *field=((Item_field*) args[0])->field;
if (((field->type() == MYSQL_TYPE_DATE) ||
(field->type() == MYSQL_TYPE_DATETIME)) &&
(field->flags & NOT_NULL_FLAG))
{
return TRUE;
}
}
}
return FALSE;
}
/**
@@ -13804,53 +13855,45 @@ internal_remove_eq_conds(THD *thd, COND *cond, Item::cond_result *cond_value)
return item;
}
}
else if (cond->type() == Item::FUNC_ITEM &&
((Item_func*) cond)->functype() == Item_func::ISNULL_FUNC)
else if (cond_is_datetime_is_null(cond))
{
Item_func_isnull *func=(Item_func_isnull*) cond;
Item **args= func->arguments();
if (args[0]->type() == Item::FIELD_ITEM)
{
Field *field=((Item_field*) args[0])->field;
/* fix to replace 'NULL' dates with '0' (shreeve@uci.edu) */
/*
See BUG#12594011
Documentation says that
SELECT datetime_notnull d FROM t1 WHERE d IS NULL
shall return rows where d=='0000-00-00'
/* fix to replace 'NULL' dates with '0' (shreeve@uci.edu) */
/*
See BUG#12594011
Documentation says that
SELECT datetime_notnull d FROM t1 WHERE d IS NULL
shall return rows where d=='0000-00-00'
Thus, for DATE and DATETIME columns defined as NOT NULL,
"date_notnull IS NULL" has to be modified to
"date_notnull IS NULL OR date_notnull == 0" (if outer join)
"date_notnull == 0" (otherwise)
Thus, for DATE and DATETIME columns defined as NOT NULL,
"date_notnull IS NULL" has to be modified to
"date_notnull IS NULL OR date_notnull == 0" (if outer join)
"date_notnull == 0" (otherwise)
*/
if (((field->type() == MYSQL_TYPE_DATE) ||
(field->type() == MYSQL_TYPE_DATETIME)) &&
(field->flags & NOT_NULL_FLAG))
{
Item *item0= new(thd->mem_root) Item_int((longlong)0, 1);
Item *eq_cond= new(thd->mem_root) Item_func_eq(args[0], item0);
if (!eq_cond)
return cond;
*/
Item **args= ((Item_func_isnull*) cond)->arguments();
Field *field=((Item_field*) args[0])->field;
Item *item0= new(thd->mem_root) Item_int((longlong)0, 1);
Item *eq_cond= new(thd->mem_root) Item_func_eq(args[0], item0);
if (!eq_cond)
return cond;
if (field->table->pos_in_table_list->is_inner_table_of_outer_join())
{
// outer join: transform "col IS NULL" to "col IS NULL or col=0"
Item *or_cond= new(thd->mem_root) Item_cond_or(eq_cond, cond);
if (!or_cond)
return cond;
cond= or_cond;
}
else
{
// not outer join: transform "col IS NULL" to "col=0"
cond= eq_cond;
}
cond->fix_fields(thd, &cond);
}
{
// outer join: transform "col IS NULL" to "col IS NULL or col=0"
Item *or_cond= new(thd->mem_root) Item_cond_or(eq_cond, cond);
if (!or_cond)
return cond;
cond= or_cond;
}
else
{
// not outer join: transform "col IS NULL" to "col=0"
cond= eq_cond;
}
cond->fix_fields(thd, &cond);
if (cond->const_item() && !cond->is_expensive())
{
*cond_value= eval_const_cond(cond) ? Item::COND_TRUE : Item::COND_FALSE;