CREATE_TIME is NULL for all partitions

[Urs Weiss]

On a database i made some events which creates and deletes partitions automatically. Creation of them works just fine. But now i saw that there was never a parition deleted.

Errors in log are:
====================
110124 1:00:11 [Warning] Event Scheduler: [root@localhost][xyz.trends_del_partition] No data - zero rows fetched, selected, or processed
110124 1:00:11 [ERROR] Event Scheduler: [root@localhost][xyz.trends_del_partition] You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'NULL' at line 1
110124 1:00:11 [Note] Event Scheduler: [root@localhost].[xyz.trends_del_partition] event execution failed.
====================


I searched a bit around and had a look into the "information_schema.PARTITIONS" table.

There i saw that all tables with partitions don't have a CREATE_TIME set (NULL). But the CREATE_TIME is used by my event to find the tables it has to delete. Most other tables without partitions have a CREATE_TIME set.


The event-body is:
====================
BEGIN
DECLARE old_partitions CHAR(64) DEFAULT '';
SELECT CONCAT( 'ALTER TABLE trends DROP PARTITION ',
GROUP_CONCAT( PARTITION_NAME ))
INTO @s
FROM information_schema.PARTITIONS
WHERE TABLE_SCHEMA=schema() AND
TABLE_NAME='trends' AND
CREATE_TIME < DATE_SUB( CURDATE(), INTERVAL 14 MONTH )
GROUP BY TABLE_NAME;

PREPARE stmt FROM @s;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
END
====================

Is there a reason partitions have no CREATE_TIME set?

MySQL Version used: 5.1.48 (CentOS 5.5 - from Remi Repository)


Thanks
Urs