Table of Contents
This chapter discusses MySQL's implementation of
user-defined partitioning. You can determine
whether your MySQL Server supports partitioning by means of a
SHOW VARIABLES
statement such as this
one:
mysql> SHOW VARIABLES LIKE '%partition%';
+-------------------+-------+
| Variable_name | Value |
+-------------------+-------+
| have_partitioning | YES |
+-------------------+-------+
1 row in set (0.00 sec)
You can also check the output of the SHOW
PLUGINS
statement, as shown here:
mysql> SHOW PLUGINS;
+------------+----------+----------------+---------+---------+
| Name | Status | Type | Library | License |
+------------+----------+----------------+---------+---------+
| binlog | ACTIVE | STORAGE ENGINE | NULL | GPL |
| partition | ACTIVE | STORAGE ENGINE | NULL | GPL |
| ARCHIVE | ACTIVE | STORAGE ENGINE | NULL | GPL |
| BLACKHOLE | ACTIVE | STORAGE ENGINE | NULL | GPL |
| CSV | ACTIVE | STORAGE ENGINE | NULL | GPL |
| FEDERATED | DISABLED | STORAGE ENGINE | NULL | GPL |
| MEMORY | ACTIVE | STORAGE ENGINE | NULL | GPL |
| InnoDB | ACTIVE | STORAGE ENGINE | NULL | GPL |
| MRG_MYISAM | ACTIVE | STORAGE ENGINE | NULL | GPL |
| MyISAM | ACTIVE | STORAGE ENGINE | NULL | GPL |
| ndbcluster | DISABLED | STORAGE ENGINE | NULL | GPL |
+------------+----------+----------------+---------+---------+
11 rows in set (0.00 sec)
If you do not see the
have_partitioning
variable with the
value YES
listed in the output of an appropriate
SHOW VARIABLES
statement, or if you
do not see the partition
plugin listed with the
value ACTIVE
for the Status
column in the output of SHOW PLUGINS
(show in bold text in the example just given), then your version of
MySQL was not built with partitioning support.
MySQL 5.5 Community binaries provided by Oracle include
partitioning support. For information about partitioning support
offered in commercial MySQL Server binaries, see MySQL
Enterprise Server 5.1 on the MySQL Web site at
http://www.mysql.com/products/enterprise/server.html
.
To enable partitioning if you are compiling MySQL 5.5
from source, the build must be configured with the
-DWITH_PARTITION_STORAGE_ENGINE
option. For more information about building MySQL, see
Section 2.11, “Installing MySQL from Source”.
If your MySQL binary is built with partitioning support, nothing
further needs to be done to enable it (for example, no special
entries are required in your my.cnf
file).
If you want to disable partitioning support, you can start the MySQL
Server with the --skip-partition
option, in which case the value of
have_partitioning
is
DISABLED
. However, if you do this, you cannot
access any partitioned tables until the server is once again
restarted without the
--skip-partition
option.
An introduction to partitioning and partitioning concepts may be found in Section 18.1, “Overview of Partitioning in MySQL”.
MySQL supports several types of partitioning, which are discussed in Section 18.2, “Partitioning Types”, as well as subpartitioning, which is described in Section 18.2.6, “Subpartitioning”.
Methods of adding, removing, and altering partitions in existing partitioned tables are covered in Section 18.3, “Partition Management”.
Table maintenance commands for use with partitioned tables are discussed in Section 18.3.3, “Maintenance of Partitions”.
The PARTITIONS
table in the
INFORMATION_SCHEMA
database provides information
about partitions and partitioned tables. See
Section 20.19, “The INFORMATION_SCHEMA PARTITIONS
Table”, for more information; for some
examples of queries against this table, see
Section 18.2.7, “How MySQL Partitioning Handles NULL
”.
The partitioning implementation in MySQL 5.5 is still undergoing development. For known issues with MySQL partitioning, see Section 18.5, “Restrictions and Limitations on Partitioning”, where we have noted these.
You may also find the following resources to be useful when working with partitioned tables.
Additional Resources. Other sources of information about user-defined partitioning in MySQL include the following:
This is the official discussion forum for those interested in or experimenting with MySQL Partitioning technology. It features announcements and updates from MySQL developers and others. It is monitored by members of the Partitioning Development and Documentation Teams.
MySQL Partitioning Architect and Lead Developer Mikael Ronström frequently posts articles here concerning his work with MySQL Partitioning and MySQL Cluster.
A MySQL news site featuring MySQL-related blogs, which should be of interest to anyone using my MySQL. We encourage you to check here for links to blogs kept by those working with MySQL Partitioning, or to have your own blog added to those covered.
MySQL 5.5 binaries are available from
http://dev.mysql.com/downloads/mysql/5.5.html.
However, for the latest partitioning bugfixes and feature additions,
you can obtain the source from our Bazaar repository. To enable
partitioning, the build must be configured with the
-DWITH_PARTITION_STORAGE_ENGINE
option. For more information about building MySQL, see
Section 2.11, “Installing MySQL from Source”. If you have problems
compiling a partitioning-enabled MySQL 5.5 build, check
the MySQL Partitioning
Forum and ask for assistance there if you do not find a
solution to your problem already posted.