MySQL修改并选取同一个表的方法
发布时间:2020-12-12 02:16:19 所属栏目:MySql教程 来源:网络整理
导读:在MySQL里,不可以修改同一个表并使用SELECT语句。可以选用JOIN来实现,例证如下 用SELECT的原语句: update spms.user set DirectReport=(select DirectReport from spms.user where UserName='%s') where UserName in (select UserName from spms.user where D
在MySQL里,不可以修改同一个表并使用SELECT语句。可以选用JOIN来实现,例证如下 用SELECT的原语句: update spms.user set DirectReport=(select DirectReport from spms.user where UserName='%s') where UserName in (select UserName from spms.user where DirectReport='%s') 选用JOIN来实现的语句: update spms.user as u1 inner join spms.user as u2 on u1.DirectReport= u2.UserName set u1.DirectReport=u2.DirectReport where u2.UserName='%s' Reference: SQL Update Syntax http://dev.mysql.com/doc/mysql/en/UPDATE.html (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |