ITEEDU

13.5.4.8. SHOW ENGINES语法

SHOW [STORAGE] ENGINES

SHOW ENGINES显示存储引擎的状态信息。对于检查一个存储引擎是否被支持,或者对于查看默认引擎是什么,本语句十分有用。SHOW TABLE TYPES是同义词,但不赞成使用。

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: NO
Comment: Supports transactions and page-level locking
*************************** 11. row ***************************
 Engine: BERKELEYDB
Support: NO
Comment: Alias for BDB
*************************** 12. row ***************************
 Engine: NDBCLUSTER
Support: DISABLED
Comment: Clustered, fault-tolerant, memory-based tables
*************************** 13. row ***************************
 Engine: NDB
Support: DISABLED
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: YES
Comment: CSV storage engine
*************************** 17. row ***************************
 Engine: FEDERATED
Support: NO
Comment: Federated MySQL storage engine
*************************** 18. row ***************************
 Engine: BLACKHOLE
Support: YES
Comment: /dev/null storage engine (anything you write to it disappears)

Support值指示某个存储引擎是否被支持,并指示哪个是默认引擎。例如,如果服务器以--default-table-type=InnoDB选项为起始,则InnoDB行的Support值为DEFAULT值。请参见第15章:存储引擎和表类型