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-rw-r--r--sql/item_subselect.cc189
1 files changed, 150 insertions, 39 deletions
diff --git a/sql/item_subselect.cc b/sql/item_subselect.cc
index 903f4c953a2..7e47de494db 100644
--- a/sql/item_subselect.cc
+++ b/sql/item_subselect.cc
@@ -969,6 +969,7 @@ Item_in_subselect::single_value_transformer(JOIN *join,
argument (reference) to fix_fields()
*/
select_lex->where= join->conds= and_items(join->conds, item);
+ select_lex->where->top_level_item();
/*
we do not check join->conds->fixed, because Item_and can't be fixed
after creation
@@ -1032,8 +1033,12 @@ Item_in_subselect::single_value_transformer(JOIN *join,
Item_subselect::trans_res
Item_in_subselect::row_value_transformer(JOIN *join)
{
- Item *item= 0;
SELECT_LEX *select_lex= join->select_lex;
+ Item *having_item= 0;
+ uint cols_num= left_expr->cols();
+ bool is_having_used= (join->having || select_lex->with_sum_func ||
+ select_lex->group_list.first ||
+ !select_lex->table_list.elements);
DBUG_ENTER("Item_in_subselect::row_value_transformer");
if (select_lex->item_list.elements != left_expr->cols())
@@ -1065,66 +1070,164 @@ Item_in_subselect::row_value_transformer(JOIN *join)
}
select_lex->uncacheable|= UNCACHEABLE_DEPENDENT;
+ if (is_having_used)
{
- uint n= left_expr->cols();
- List_iterator_fast<Item> li(select_lex->item_list);
- for (uint i= 0; i < n; i++)
+ /*
+ (l1, l2, l3) IN (SELECT v1, v2, v3 ... HAVING having) =>
+ EXISTS (SELECT ... HAVING having and
+ (l1 = v1 or is null v1) and
+ (l2 = v2 or is null v2) and
+ (l3 = v3 or is null v3) and
+ is_not_null_test(v1) and
+ is_not_null_test(v2) and
+ is_not_null_test(v3))
+ where is_not_null_test used to register nulls in case if we have
+ not found matching to return correct NULL value
+ */
+ Item *item_having_part2= 0;
+ for (uint i= 0; i < cols_num; i++)
{
DBUG_ASSERT(left_expr->fixed && select_lex->ref_pointer_array[i]->fixed);
if (select_lex->ref_pointer_array[i]->
check_cols(left_expr->el(i)->cols()))
DBUG_RETURN(RES_ERROR);
- Item *func= new Item_ref_null_helper(&select_lex->context,
- this,
- select_lex->ref_pointer_array+i,
- (char *) "<no matter>",
- (char *) "<list ref>");
- func=
- eq_creator.create(new Item_direct_ref(&select_lex->context,
- (*optimizer->get_cache())->
- addr(i),
- (char *)"<no matter>",
- (char *)in_left_expr_name),
- func);
- item= and_items(item, func);
+ Item *item_eq=
+ new Item_func_eq(new
+ Item_direct_ref(&select_lex->context,
+ (*optimizer->get_cache())->
+ addr(i),
+ (char *)"<no matter>",
+ (char *)in_left_expr_name),
+ new
+ Item_direct_ref(&select_lex->context,
+ select_lex->ref_pointer_array + i,
+ (char *)"<no matter>",
+ (char *)"<list ref>")
+ );
+ Item *item_isnull=
+ new Item_func_isnull(new
+ Item_direct_ref(&select_lex->context,
+ select_lex->
+ ref_pointer_array+i,
+ (char *)"<no matter>",
+ (char *)"<list ref>")
+ );
+ having_item=
+ and_items(having_item,
+ new Item_cond_or(item_eq, item_isnull));
+ item_having_part2=
+ and_items(item_having_part2,
+ new
+ Item_is_not_null_test(this,
+ new
+ Item_direct_ref(&select_lex->context,
+ select_lex->
+ ref_pointer_array + i,
+ (char *)"<no matter>",
+ (char *)"<list ref>")
+ )
+ );
+ item_having_part2->top_level_item();
}
+ having_item= and_items(having_item, item_having_part2);
+ having_item->top_level_item();
}
- if (join->having || select_lex->with_sum_func ||
- select_lex->group_list.first ||
- !select_lex->table_list.elements)
+ else
{
/*
- AND can't be changed during fix_fields()
- we can assign select_lex->having here, and pass 0 as last
- argument (reference) to fix_fields()
+ (l1, l2, l3) IN (SELECT v1, v2, v3 ... WHERE where) =>
+ EXISTS (SELECT ... WHERE where and
+ (l1 = v1 or is null v1) and
+ (l2 = v2 or is null v2) and
+ (l3 = v3 or is null v3)
+ HAVING is_not_null_test(v1) and
+ is_not_null_test(v2) and
+ is_not_null_test(v3))
+ where is_not_null_test register NULLs values but reject rows
+
+ in case when we do not need correct NULL, we have simplier construction:
+ EXISTS (SELECT ... WHERE where and
+ (l1 = v1) and
+ (l2 = v2) and
+ (l3 = v3)
*/
- select_lex->having= join->having= and_items(join->having, item);
- select_lex->having_fix_field= 1;
+ Item *where_item= 0;
+ for (uint i= 0; i < cols_num; i++)
+ {
+ Item *item, *item_isnull;
+ DBUG_ASSERT(left_expr->fixed && select_lex->ref_pointer_array[i]->fixed);
+ if (select_lex->ref_pointer_array[i]->
+ check_cols(left_expr->el(i)->cols()))
+ DBUG_RETURN(RES_ERROR);
+ item=
+ new Item_func_eq(new
+ Item_direct_ref(&select_lex->context,
+ (*optimizer->get_cache())->
+ addr(i),
+ (char *)"<no matter>",
+ (char *)in_left_expr_name),
+ new
+ Item_direct_ref(&select_lex->context,
+ select_lex->
+ ref_pointer_array+i,
+ (char *)"<no matter>",
+ (char *)"<list ref>")
+ );
+ if (!abort_on_null)
+ {
+ having_item=
+ and_items(having_item,
+ new
+ Item_is_not_null_test(this,
+ new
+ Item_direct_ref(&select_lex->context,
+ select_lex->
+ ref_pointer_array + i,
+ (char *)"<no matter>",
+ (char *)"<list ref>")
+ )
+ );
+ item_isnull= new
+ Item_func_isnull(new
+ Item_direct_ref(&select_lex->context,
+ select_lex->
+ ref_pointer_array+i,
+ (char *)"<no matter>",
+ (char *)"<list ref>")
+ );
+
+ item= new Item_cond_or(item, item_isnull);
+ }
+
+ where_item= and_items(where_item, item);
+ }
/*
- join->having can't be fixed after creation, so we do not check
- join->having->fixed
+ AND can't be changed during fix_fields()
+ we can assign select_lex->where here, and pass 0 as last
+ argument (reference) to fix_fields()
*/
- if (join->having->fix_fields(thd, 0))
- {
- select_lex->having_fix_field= 0;
+ select_lex->where= join->conds= and_items(join->conds, where_item);
+ select_lex->where->top_level_item();
+ if (join->conds->fix_fields(thd, 0))
DBUG_RETURN(RES_ERROR);
- }
- select_lex->having_fix_field= 0;
}
- else
+ if (having_item)
{
+ bool res;
+ select_lex->having= join->having= and_items(join->having, having_item);
+ select_lex->having->top_level_item();
/*
AND can't be changed during fix_fields()
we can assign select_lex->having here, and pass 0 as last
argument (reference) to fix_fields()
*/
- select_lex->where= join->conds= and_items(join->conds, item);
- /*
- join->conds can't be fixed after creation, so we do not check
- join->conds->fixed
- */
- if (join->conds->fix_fields(thd, 0))
+ select_lex->having_fix_field= 1;
+ res= join->having->fix_fields(thd, 0);
+ select_lex->having_fix_field= 0;
+ if (res)
+ {
DBUG_RETURN(RES_ERROR);
+ }
}
DBUG_RETURN(RES_OK);
@@ -1271,6 +1374,14 @@ void Item_allany_subselect::print(String *str)
}
+void subselect_engine::set_thd(THD *thd_arg)
+{
+ thd= thd_arg;
+ if (result)
+ result->set_thd(thd_arg);
+}
+
+
subselect_single_select_engine::
subselect_single_select_engine(st_select_lex *select,
select_subselect *result,
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