Bug #55602 select count(*) + order by desc + limit + partitioning delivers not all results

• Submitted: 28 Jul 2010 13:35
• Modified: 28 Aug 2010 13:59
• Reporter: Rene Eng
• Status: No Feedback
• Category: MySQL Server
• Severity: S2 (Serious)
• Version: 5.1.46
• OS: Solaris (10, 64 bit)
• CPU Architecture: Any

[28 Jul 2010 13:35] Rene Eng

Description:
The following query returns ~ 12000 results on my partitioned table:
select count(*), field1, field2 from MyTable where field3 = 88 group by 2, 3 order by 1 desc;
--> 12003 rows in set (1.00 sec)

The same query with limit returns only 1 result!
select count(*), field1, field2 from MyTable where field3 = 88 group by 2, 3 order by 1 desc limit [2..62];
--> 1 row in set (0.13 sec)

The same result is returned for all limits in the range 2 .. 62. With a limit >= 63, the result is correct:
--> 63 rows in set (0.93 sec)

The result is also correct if the 'order by' clause is omitted:
select count(*), field1, field2 from MyTable where field3 = 88 group by 2, 3 limit 20;
--> 20 rows in set (0.23 sec)

On a non-partitioned table the requests work all okay.

How to repeat:
Create a partitioned table, insert data and try the requests as described.

Suggested fix:
Always return the correct (maximum) number of results.

[28 Jul 2010 13:59] Valeriy Kravchuk

Please, check if the same problem happens with current version, 5.1.49. Send dump of the table in case of the same bug with 5.1.49.

[28 Aug 2010 23:00] Bugs System

No feedback was provided for this bug for over a month, so it is
being suspended automatically. If you are able to provide the
information that was originally requested, please do so and change
the status of the bug back to "Open".