Table of Contents
This chapter discusses MySQL's implementation of user-defined partitioning.
As of MySQL 5.7.17, the generic partitioning handler in the MySQL
server is deprecated, and is removed in MySQL 8.0, when
the storage engine used for a given table is expected to provide
its own (“native”) partitioning handler. Currently,
only the InnoDB
and
NDB
storage engines do this.
Use of tables with nonnative partitioning results in an
ER_WARN_DEPRECATED_SYNTAX
warning.
In MySQL 5.7.17 through 5.7.20, the server automatically performs
a check at startup to identify tables that use nonnative
partitioning; for any that are found, the server writes a message
to its error log. To disable this check, use the
--disable-partition-engine-check
option. In MySQL 5.7.21 and later, this check is
not performed; in these versions, you must
start the server with
--disable-partition-engine-check=false
,
if you wish for the server to check for tables using the generic
partitioning handler (Bug #85830, Bug #25846957).
To prepare for migration to MySQL 8.0, any table with
nonnative partitioning should be changed to use an engine that
provides native partitioning, or be made nonpartitioned. For
example, to change a table to InnoDB
, execute
this statement:
ALTER TABLE table_name ENGINE = INNODB;
You can determine whether your MySQL Server supports partitioning by
checking the output of the SHOW
PLUGINS
statement, like this:
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)
You can also check the Information Schema
PLUGINS
table with a query similar to
this one:
mysql> SELECT
-> PLUGIN_NAME as Name,
-> PLUGIN_VERSION as Version,
-> PLUGIN_STATUS as Status
-> FROM INFORMATION_SCHEMA.PLUGINS
-> WHERE PLUGIN_TYPE='STORAGE ENGINE';
+--------------------+---------+--------+
| Name | Version | Status |
+--------------------+---------+--------+
| binlog | 1.0 | ACTIVE |
| CSV | 1.0 | ACTIVE |
| MEMORY | 1.0 | ACTIVE |
| MRG_MYISAM | 1.0 | ACTIVE |
| MyISAM | 1.0 | ACTIVE |
| PERFORMANCE_SCHEMA | 0.1 | ACTIVE |
| BLACKHOLE | 1.0 | ACTIVE |
| ARCHIVE | 3.0 | ACTIVE |
| InnoDB | 5.7 | ACTIVE |
| partition | 1.0 | ACTIVE |
+--------------------+---------+--------+
10 rows in set (0.00 sec)
In either case, if you do not see the partition
plugin listed with the value ACTIVE
for the
Status
column in the output (shown in bold text
in each of the examples just given), then your version of MySQL was
not built with partitioning support.
MySQL 5.7 Community binaries provided by Oracle include partitioning support. For information about partitioning support offered in MySQL Enterprise Edition binaries, see Chapter 28, MySQL Enterprise Edition.
To enable partitioning if you are compiling MySQL 5.7
from source, the build must be configured with the
-DWITH_PARTITION_STORAGE_ENGINE
option. For more information, see
Section 2.8, “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. When partitioning support is disabled, you can see any
existing partitioned tables and drop them (although doing this is
not advised), but you cannot otherwise manipulate them or access
their data.
See Section 22.1, “Overview of Partitioning in MySQL”, for an introduction to partitioning and partitioning concepts.
MySQL supports several types of partitioning as well as subpartitioning; see Section 22.2, “Partitioning Types”, and Section 22.2.6, “Subpartitioning”.
Section 22.3, “Partition Management”, covers methods of adding, removing, and altering partitions in existing partitioned tables.
Section 22.3.4, “Maintenance of Partitions”, discusses table maintenance commands for use with partitioned tables.
The PARTITIONS
table in the
INFORMATION_SCHEMA
database provides information
about partitions and partitioned tables. See
Section 24.3.16, “The INFORMATION_SCHEMA PARTITIONS Table”, for more
information; for some examples of queries against this table, see
Section 22.2.7, “How MySQL Partitioning Handles NULL”.
For known issues with partitioning in MySQL 5.7, see Section 22.6, “Restrictions and Limitations on Partitioning”.
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.
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 5.7 binaries are available from
https://dev.mysql.com/downloads/mysql/5.7.html.
However, for the latest partitioning bugfixes and feature additions,
you can obtain the source from our GitHub repository. To enable
partitioning, the build must be configured with the
-DWITH_PARTITION_STORAGE_ENGINE
option. For more information about building MySQL, see
Section 2.8, “Installing MySQL from Source”. If you have problems
compiling a partitioning-enabled MySQL 5.7 build, check
the MySQL Partitioning
Forum and ask for assistance there if you do not find a
solution to your problem already posted.