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MySQL 5.5 Reference Manual :: 17 Partitioning :: 17.5 Restrictions and Limitations on Partitioning :: 17.5.3 Partitioning Limitations Relating to Functions
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17.5.3. Partitioning Limitations Relating to Functions

This section discusses limitations in MySQL Partitioning relating specifically to functions used in partitioning expressions.

Only the MySQL functions shown in the following table are supported in partitioning expressions:

ABS() CEILING() (see CEILING() and FLOOR()) DAY()
DAYOFMONTH() DAYOFWEEK() DAYOFYEAR()
DATEDIFF() EXTRACT() FLOOR() (see CEILING() and FLOOR())
HOUR() MICROSECOND() MINUTE()
MOD() MONTH() QUARTER()
SECOND() TIME_TO_SEC() TO_DAYS()
TO_SECONDS() (implemented in MySQL 5.5.0) UNIX_TIMESTAMP() (permitted in MySQL 5.5.1 and later, with TIMESTAMP columns) WEEKDAY()
YEAR()   YEARWEEK()

Note

In MySQL 5.5, partition pruning is supported only for the TO_DAYS(), TO_SECONDS(), and YEAR() functions. See Section 17.4, “Partition Pruning”, for more information.

CEILING() and FLOOR().  Each of these functions returns an integer only if it is passed an integer argument. This means, for example, that the following CREATE TABLE statement fails with an error, as shown here: 

mysql> CREATE TABLE t (c FLOAT) PARTITION BY LIST( FLOOR(c) )(
    ->     PARTITION p0 VALUES IN (1,3,5),
    ->     PARTITION p1 VALUES IN (2,4,6)
    -> );
ERROR 1490 (HY000): The PARTITION function returns the wrong type

See Section 11.5.2, “Mathematical Functions”, for more information about the return types of these functions.