Partitioning by Date

[Christian Starka]

I want to use partitioning by range, based on a TIMESTAMP(14) column, using the year-function. But when explaining the query, i can see:
- always all partitions involved, independently from the year-range that i'm querying
- some special characters in front of the first created partitions.

Does anybody know, if there are restricitions on the format of the base-column that i can use for partitioning.

i'm using 5.1.11beta on Win2003 Server, query browser.

CREATE TABLE `T` (
`rowid` BIGINT UNSIGNED NOT NULL,
`ref` BIGINT UNSIGNED NOT NULL,
`lastchange` TIMESTAMP(14) DEFAULT '0000-00-00 00:00:00',
`msec` INTEGER(3) UNSIGNED,
`value` FLOAT,
`status` BIGINT UNSIGNED,
`lastchange_event` TIMESTAMP(14),
`msec_event` INTEGER(3) UNSIGNED,
`zaediff` FLOAT,
`target` VARCHAR(1) DEFAULT 'C',
`expire` TIMESTAMP(14),
`seq_num` BIGINT UNSIGNED,
UNIQUE `UK_REF_LASTCHANGE`(`ref`,`lastchange`)
) ENGINE=MyISAM
PARTITION BY RANGE ( YEAR(lastchange)) (
PARTITION p0 VALUES LESS THAN (2006),
PARTITION p1 VALUES LESS THAN (2007),
PARTITION p2 VALUES LESS THAN (2008),
PARTITION p3 VALUES LESS THAN (2009),
PARTITION p4 VALUES LESS THAN (2010)
);