|
Hi Roman, do you mean bug - results in a wrong order? Please add an example.
create or replace table t (a int, b int, c int);
|
insert into t values (2,2,4), (2,1,5), (2,1,4),(2,2,6),(8,3,4),(1,6,1),(2,3,4),(5,3,2);
|
select a,b,sum(c) from t group by a,b order by a desc;
|
explain extended select a,b,sum(c) from t group by a,b order by a desc;
|
|
MariaDB [test]> select a,b,sum(c) from t group by a,b order by a desc;
|
+------+------+--------+
|
| a | b | sum(c) |
|
+------+------+--------+
|
| 8 | 3 | 4 |
|
| 5 | 3 | 2 |
|
| 2 | 1 | 9 |
|
| 2 | 2 | 10 |
|
| 2 | 3 | 4 |
|
| 1 | 6 | 1 |
|
+------+------+--------+
|
6 rows in set (0.000 sec)
|
|
MariaDB [test]> explain extended select a,b,sum(c) from t group by a,b order by a desc;
|
+------+-------------+-------+------+---------------+------+---------+------+------+----------+---------------------------------+
|
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | filtered | Extra |
|
+------+-------------+-------+------+---------------+------+---------+------+------+----------+---------------------------------+
|
| 1 | SIMPLE | t | ALL | NULL | NULL | NULL | NULL | 8 | 100.00 | Using temporary; Using filesort |
|
+------+-------------+-------+------+---------------+------+---------+------+------+----------+---------------------------------+
|
1 row in set, 1 warning (0.000 sec)
|
|
Note (Code 1003): select `test`.`t`.`a` AS `a`,`test`.`t`.`b` AS `b`,sum(`test`.`t`.`c`) AS `sum(c)` from `test`.`t` group by `test`.`t`.`a` desc,`test`.`t`.`b` order by `test`.`t`.`a` desc
|
|