MYSQL回收碎片空间

一般大批量删除或者更新后会产生碎片,需要回收

以MYSQL5.7为例

查看碎片大小 :

SELECT TABLE_NAME, ROUND((DATA_LENGTH+INDEX_LENGTH)/1024/1024,2) AS total_mb,ROUND(DATA_FREE/1024/1024,2) AS free_mb FROM information_schema.TABLES WHERE TABLE_NAME='m_log';

回收碎片并更新统计信息:

ALTER TABLE m_log ENGINE=InnoDB, ALGORITHM=INPLACE, LOCK=NONE;

ANALYZE TABLE m_log;