MySql安全模式删除

Question

DROP TABLE IF EXISTS `session`;
CREATE TABLE `session` (
`Id` varchar(128) NOT NULL,
`Browser` varchar(128) NOT NULL,
`IpAddress` varchar(128) NOT NULL,
`UserId` varchar(128) NOT NULL,
`CreatedAt` datetime DEFAULT NULL,
`ModifiedAt` datetime DEFAULT NULL,
`CreatedBy` varchar(256) DEFAULT NULL,
`ModifiedBy` varchar(256) DEFAULT NULL,
PRIMARY KEY (`Id`)
);


DELETE FROM session 
WHERE Id IN (SELECT * FROM (SELECT Id FROM session WHERE CreatedAt > NOW()) AS temp);

DELETE FROM session 
WHERE Id !='' AND Id IN (SELECT * FROM (SELECT Id FROM session WHERE Browser = "Mozilla") AS temp);

Answer 1

也许您可以尝试在使用键的where子句中添加一个虚拟条件，例如。

DELETE FROM session 
WHERE Id <> '' AND
      Id IN (SELECT * FROM (SELECT Id FROM session WHERE CreatedAt > NOW()) AS temp);

假设主键列id始终不是空字符串，那么添加此条件不会影响您的删除逻辑。

正如您提到的,您还可以通过以下方式在会话中禁用安全模式：

SET SQL_SAFE_UPDATES = 0;

SET SQL_SAFE_UPDATES = 1;