13.7.5.13 SHOW ENGINES Syntax

SHOW [STORAGE] ENGINES

SHOW ENGINES displays status information about the server's storage engines. This is particularly useful for checking whether a storage engine is supported, or to see what the default engine is. SHOW TABLE TYPES is a synonym, but is deprecated and is removed in MySQL 5.5.

mysql> SHOW ENGINES\G
*************************** 1. row ***************************
 Engine: MyISAM
Support: DEFAULT
Comment: Default engine as of MySQL 3.23 with great performance
*************************** 2. row ***************************
 Engine: MEMORY
Support: YES
Comment: Hash based, stored in memory, useful for temporary tables
*************************** 3. row ***************************
 Engine: HEAP
Support: YES
Comment: Alias for MEMORY
*************************** 4. row ***************************
 Engine: MERGE
Support: YES
Comment: Collection of identical MyISAM tables
*************************** 5. row ***************************
 Engine: MRG_MYISAM
Support: YES
Comment: Alias for MERGE
*************************** 6. row ***************************
 Engine: ISAM
Support: NO
Comment: Obsolete storage engine, now replaced by MyISAM
*************************** 7. row ***************************
 Engine: MRG_ISAM
Support: NO
Comment: Obsolete storage engine, now replaced by MERGE
*************************** 8. row ***************************
 Engine: InnoDB
Support: YES
Comment: Supports transactions, row-level locking, and foreign keys
*************************** 9. row ***************************
 Engine: INNOBASE
Support: YES
Comment: Alias for INNODB
*************************** 10. row ***************************
 Engine: BDB
Support: YES
Comment: Supports transactions and page-level locking
*************************** 11. row ***************************
 Engine: BERKELEYDB
Support: YES
Comment: Alias for BDB
*************************** 12. row ***************************
 Engine: NDBCLUSTER
Support: NO
Comment: Clustered, fault-tolerant, memory-based tables
*************************** 13. row ***************************
 Engine: NDB
Support: NO
Comment: Alias for NDBCLUSTER
*************************** 14. row ***************************
 Engine: EXAMPLE
Support: NO
Comment: Example storage engine
*************************** 15. row ***************************
 Engine: ARCHIVE
Support: YES
Comment: Archive storage engine
*************************** 16. row ***************************
 Engine: CSV
Support: NO
Comment: CSV storage engine
*************************** 17. row ***************************
 Engine: FEDERATED
Support: YES
Comment: Federated MySQL storage engine
*************************** 18. row ***************************
 Engine: BLACKHOLE
Support: YES
Comment: /dev/null storage engine (anything you write to it disappears)

The output from SHOW ENGINES may vary according to the MySQL version used and other factors. The values shown in the Support column indicate the server's level of support for the storage engine, as shown in the following table.

ValueMeaning
YESThe engine is supported and is active
DEFAULTLike YES, plus this is the default engine
NOThe engine is not supported
DISABLEDThe engine is supported but has been disabled

A value of NO means that the server was compiled without support for the engine, so it cannot be activated at runtime.

A value of DISABLED occurs either because the server was started with an option that disables the engine, or because not all options required to enable it were given. In the latter case, the error log file should contain a reason indicating why the option is disabled. See Section 5.2.1, “The Error Log”.

You might also see DISABLED for a storage engine if the server was compiled to support it, but was started with a --skip-engine_name option. For example, --skip-innodb disables the InnoDB engine. For the NDBCLUSTER storage engine, DISABLED means the server was compiled with support for MySQL Cluster, but was not started with the --ndbcluster option.

All MySQL servers support MyISAM tables, because MyISAM is the default storage engine. It is not possible to disable MyISAM.