database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-07-30 16:24:05 +03:00
Code Activity

MDEV-16359 wrong result (extra rows) on the query with UNION and brackets

Browse Source 
Due to an obvious bug in st_select_lex_unit::reset_distinct() a union
without duplicates of more than 2 selects could return a result set
containing duplicate rows if this union was enclosed in ().
This commit is contained in:
Igor Babaev
2018-08-03 23:27:24 -07:00
parent 980aa3e71d
commit 0f9efd54ce
3 changed files with 20 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
mysql-test/main/brackets.result
View File

@ -207,4 +207,16 @@ a b
1 100
3 30
drop table t1;
#
# MDEV-16359: union with 3 selects in brackets
#
select 1 union select 1 union select 1;
1
1
(select 1 union select 1 union select 1);
1
1
((select 1) union (select 1) union (select 1));
1
1
# End of 10.4 tests

8
mysql-test/main/brackets.test
View File

@ -80,5 +80,13 @@ select a,b from t1 order by 1 limit 3;
drop table t1;
--echo #
--echo # MDEV-16359: union with 3 selects in brackets
--echo #
select 1 union select 1 union select 1;
(select 1 union select 1 union select 1);
((select 1) union (select 1) union (select 1));
--echo # End of 10.4 tests

1
sql/sql_lex.cc
View File

@ -8763,7 +8763,6 @@ void st_select_lex_unit::reset_distinct()
if (sl->distinct)
{
union_distinct= sl;
return;
}
}
}