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MySQL 5.7 Reference Manual
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14.7.5.16 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. This information can also be obtained from the INFORMATION_SCHEMA ENGINES table. See Section 22.6, “The INFORMATION_SCHEMA ENGINES Table”.

mysql> SHOW ENGINES\G
*************************** 1. row ***************************
      Engine: InnoDB
     Support: DEFAULT
     Comment: Supports transactions, row-level locking, and foreign keys
Transactions: YES
          XA: YES
  Savepoints: YES
*************************** 2. row ***************************
      Engine: MRG_MYISAM
     Support: YES
     Comment: Collection of identical MyISAM tables
Transactions: NO
          XA: NO
  Savepoints: NO
*************************** 3. row ***************************
      Engine: MEMORY
     Support: YES
     Comment: Hash based, stored in memory, useful for temporary tables
Transactions: NO
          XA: NO
  Savepoints: NO
*************************** 4. row ***************************
      Engine: BLACKHOLE
     Support: YES
     Comment: /dev/null storage engine (anything you write to it disappears)
Transactions: NO
          XA: NO
  Savepoints: NO
*************************** 5. row ***************************
      Engine: MyISAM
     Support: YES
     Comment: MyISAM storage engine
Transactions: NO
          XA: NO
  Savepoints: NO
*************************** 6. row ***************************
      Engine: CSV
     Support: YES
     Comment: CSV storage engine
Transactions: NO
          XA: NO
  Savepoints: NO
*************************** 7. row ***************************
      Engine: ARCHIVE
     Support: YES
     Comment: Archive storage engine
Transactions: NO
          XA: NO
  Savepoints: NO
*************************** 8. row ***************************
      Engine: PERFORMANCE_SCHEMA
     Support: YES
     Comment: Performance Schema
Transactions: NO
          XA: NO
  Savepoints: NO
*************************** 9. row ***************************
      Engine: FEDERATED
     Support: YES
     Comment: Federated MySQL storage engine
Transactions: NO
          XA: NO
  Savepoints: NO

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 enabled 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 6.4.2, “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.

All MySQL servers support MyISAM tables. It is not possible to disable MyISAM.

The Transactions, XA, and Savepoints columns indicate whether the storage engine supports transactions, XA transactions, and savepoints, respectively.


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