#查詢是否鎖表 SHOW OPEN TABLES WHERE IN_USE>0; #查詢進程 SHOW PROCESSLIST #殺死進程(通常到這一步就解鎖了) KILL ID; #查看正運行的事務 SELECT * FROM INFORMATION_SCHEMA.INNODB_TRX;; #查看正在鎖的事務 SELECT * FROM INFORMATION_SCHEMA.INNODB_LOCKS; #查看等待鎖的事務 SELECT * FROM INFORMATION_SCHEMA.INNODB_LOCK_WAITS; #解鎖表 UNLOCK TABLES;
1)表中建立索引,SELECT ... WHERE 字段(必須是索引,不然行鎖無效)。spa
注:InnoDB的行鎖是針對索引加的鎖,不是針對記錄加的鎖,而且該索引不能失效,不然都會從行鎖升級爲表鎖。.net
二、必需要有事務,這樣纔是行鎖(排他鎖)。code
三、在SELECT語句後面加上FOR UPDATE。blog
#加事務 START TRANSACTION; #加鎖 SELECT * FROM EMP WHERE ID<=10 FOR UPDATE; #解析 EXPLAIN SELECT * FROM EMP WHERE ID<=10 FOR UPDATE; #睡眠 SELECT SLEEP(3); #提交 COMMIT; #加事務 START TRANSACTION; #加鎖 SELECT * FROM EMP WHERE ID BETWEEN 11 AND 20 FOR UPDATE; #解析 EXPLAIN SELECT * FROM EMP WHERE ID BETWEEN 11 AND 20 FOR UPDATE; #提交 COMMIT;
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