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MySQL 8.0 Reference Manual
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13.7.7.16 SHOW ENGINES Statement

SHOW [STORAGE] ENGINES

显示引擎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.

For information about MySQL storage engines, seeChapter 15,The InnoDB Storage Engine, andChapter 16,Alternative Storage Engines.

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

The output from显示引擎may vary according to the MySQL version used and other factors.

显示引擎output has these columns:

  • Engine

    The name of the storage engine.

  • Support

    The server's level of support for the storage engine, as shown in the following table.

    Value Meaning
    YES The engine is supported and is active
    DEFAULT LikeYES, plus this is the default engine
    NO The engine is not supported
    DISABLED The engine is supported but has been disabled

    A value ofNOmeans that the server was compiled without support for the engine, so it cannot be enabled at runtime.

    A value ofDISABLEDoccurs 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 should contain a reason indicating why the option is disabled. SeeSection 5.4.2, “The Error Log”.

    You might also seeDISABLEDfor a storage engine if the server was compiled to support it, but was started with a--skip-engine_nameoption. For theNDBstorage engine,DISABLEDmeans the server was compiled with support for NDB Cluster, but was not started with the--ndbclusteroption.

    All MySQL servers supportMyISAMtables. It is not possible to disableMyISAM.

  • Comment

    A brief description of the storage engine.

  • Transactions

    Whether the storage engine supports transactions.

  • XA

    Whether the storage engine supports XA transactions.

  • 保存点s

    Whether the storage engine supports savepoints.

Storage engine information is also available from theINFORMATION_SCHEMAENGINEStable. SeeSection 26.3.13, “The INFORMATION_SCHEMA ENGINES Table”.