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MDEV-30706 Different results of selects from view and CTE with same definition

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MDEV-30668 Set function aggregated in outer select used in view definition

This patch fixes two bugs concerning views whose specifications contain
subqueries with set functions aggregated in outer selects.
Due to the first bug those such views that have implicit grouping were
considered as mergeable. This led to wrong result sets for selects from
these views.
Due to the second bug the aggregation select was determined incorrectly and
this led to bogus error messages.
The patch added several test cases for these two bugs and for four other
duplicate bugs.
The patch also enables view-protocol for many other test cases.

Approved by Oleksandr Byelkin <sanja@mariadb.com>
This commit is contained in:
Igor Babaev
2023-03-01 22:49:27 -08:00
parent a6a906d766
commit ccec9b1de9
23 changed files with 2021 additions and 722 deletions
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43
sql/sql_lex.cc
View File

@ -3284,40 +3284,45 @@ LEX::LEX()
}
bool LEX::can_be_merged()
{
return unit.can_be_merged();
}
/*
Check whether the merging algorithm can be used on this VIEW
Check whether the merging algorithm can be used for this unit
SYNOPSIS
LEX::can_be_merged()
st_select_lex_unit::can_be_merged()
DESCRIPTION
We can apply merge algorithm if it is single SELECT view with
subqueries only in WHERE clause (we do not count SELECTs of underlying
views, and second level subqueries) and we have not grpouping, ordering,
HAVING clause, aggregate functions, DISTINCT clause, LIMIT clause and
several underlying tables.
We can apply merge algorithm for a unit if it is single SELECT with
subqueries only in WHERE clauses or in ON conditions or in select list
(we do not count SELECTs of underlying views/derived tables/CTEs and
second level subqueries) and we have no grouping, ordering, HAVING
clause, aggregate functions, DISTINCT clause, LIMIT clause.
RETURN
FALSE - only temporary table algorithm can be used
TRUE - merge algorithm can be used
*/
bool LEX::can_be_merged()
bool st_select_lex_unit::can_be_merged()
{
// TODO: do not forget implement case when select_lex.table_list.elements==0
/* find non VIEW subqueries/unions */
bool selects_allow_merge= (first_select_lex()->next_select() == 0 &&
!(first_select_lex()->uncacheable &
bool selects_allow_merge= (first_select()->next_select() == 0 &&
!(first_select()->uncacheable &
UNCACHEABLE_RAND));
if (selects_allow_merge)
{
for (SELECT_LEX_UNIT *tmp_unit= first_select_lex()->first_inner_unit();
for (SELECT_LEX_UNIT *tmp_unit= first_select()->first_inner_unit();
tmp_unit;
tmp_unit= tmp_unit->next_unit())
{
if (tmp_unit->first_select()->parent_lex == this &&
(tmp_unit->item != 0 &&
if ((tmp_unit->item != 0 &&
(tmp_unit->item->place() != IN_WHERE &&
tmp_unit->item->place() != IN_ON &&
tmp_unit->item->place() != SELECT_LIST)))
@ -3329,12 +3334,12 @@ bool LEX::can_be_merged()
}
return (selects_allow_merge &&
first_select_lex()->group_list.elements == 0 &&
first_select_lex()->having == 0 &&
first_select_lex()->with_sum_func == 0 &&
first_select_lex()->table_list.elements >= 1 &&
!(first_select_lex()->options & SELECT_DISTINCT) &&
first_select_lex()->select_limit == 0);
first_select()->group_list.elements == 0 &&
first_select()->having == 0 &&
first_select()->with_sum_func == 0 &&
first_select()->table_list.elements >= 1 &&
!(first_select()->options & SELECT_DISTINCT) &&
first_select()->select_limit == 0);
}