MySQL Bugs: #9800: Rollup crash with distinct avg()

Bug #9800	Rollup crash with distinct avg()
Submitted:	11 Apr 2005 0:33	Modified:	17 May 2005 20:35
Reporter:	Peter Gulutzan	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: Optimizer	Severity:	S3 (Non-critical)
Version:	5.0.5-beta-debug	OS:	Linux (SUSE 9.2)
Assigned to:	Jani Tolonen	CPU Architecture:	Any

Description:
If I have a table with at least two rows, one of which contains NULL, and I do SELECT DISTINCT AVG(...) ... GROUP BY ... WITH ROLLUP, crash.

I know that "distinct avg()" sounds similar to "avg(distinct)" which is bug#9799, but the circumstances are different.

How to repeat:
mysql> create table t6 (s1 int);
Query OK, 0 rows affected (0.01 sec)

mysql> insert into t6 values (null),(1);
Query OK, 2 rows affected (0.00 sec)
Records: 2  Duplicates: 0  Warnings: 0

mysql> select distinct avg(s1) as x from t5 group by s1 with rollup;
ERROR 2013 (HY000): Lost connection to MySQL server during query

Thank you for the bug report.
The last query in the test case changed the table name t5->t6:

select distinct avg(s1) as x from t6 group by s1 with rollup;

Thank you for your bug report. This issue has been committed to our
source repository of that product and will be incorporated into the
next release.

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available version, including the bugfix, yourself. More information 
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Noted in 5.0.6 changelog.