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Fix for BUG#14920 Ordering aggregated result sets corrupts resultset.

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The cause of the bug was the use of end_write_group instead of end_write
in the case when ORDER BY required a temporary table, which didn't take
into account the fact that loose index scan already computes the result
of MIN/MAX aggregate functions (and performs grouping).

The solution is to call end_write instead of end_write_group and to add
the MIN/MAX functions to the list of regular functions so that their
values are inserted into the temporary table.
This commit is contained in:
timour@mysql.com
2005-11-30 12:52:12 +02:00
parent 519139b63a
commit 999a73ace5
6 changed files with 113 additions and 12 deletions
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31
mysql-test/r/group_min_max.result
View File

@@ -2002,3 +2002,34 @@ a count(a)
1 1
NULL 1
drop table t1;
create table t1 (c1 int not null,c2 int not null, primary key(c1,c2));
insert into t1 (c1,c2) values
(10,1),(10,2),(10,3),(20,4),(20,5),(20,6),(30,7),(30,8),(30,9);
select distinct c1, c2 from t1 order by c2;
c1 c2
10 1
10 2
10 3
20 4
20 5
20 6
30 7
30 8
30 9
select c1,min(c2) as c2 from t1 group by c1 order by c2;
c1 c2
10 1
20 4
30 7
select c1,c2 from t1 group by c1,c2 order by c2;
c1 c2
10 1
10 2
10 3
20 4
20 5
20 6
30 7
30 8
30 9
drop table t1;

13
mysql-test/t/group_min_max.test
View File

@@ -693,3 +693,16 @@ create table t1(a int, key(a)) engine=innodb;
insert into t1 values(1);
select a, count(a) from t1 group by a with rollup;
drop table t1;
#
# Bug #14920 Ordering aggregated result sets with composite primary keys
# corrupts resultset
#
create table t1 (c1 int not null,c2 int not null, primary key(c1,c2));
insert into t1 (c1,c2) values
(10,1),(10,2),(10,3),(20,4),(20,5),(20,6),(30,7),(30,8),(30,9);
select distinct c1, c2 from t1 order by c2;
select c1,min(c2) as c2 from t1 group by c1 order by c2;
select c1,c2 from t1 group by c1,c2 order by c2;
drop table t1;