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SQL中使用update inner join和delete inner join

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Jun 07, 2016 pm 05:44 PM

deletejoinupdateuse

SQL中使用update inner join和delete inner join Update Update XXX set XXX where 这种写法大家肯定都知道，才发现update和delete居然支持inner join的update方式，这个在表间关联来做更新和删除操作非常有用.列子:Sql代码 update tb_User tb_User usr inne

SQL中使用update inner join和delete inner join

Update Update XXX set XXX where 这种写法大家肯定都知道，才发现update和delete居然支持inner join的update方式，这个在表间关联来做更新和删除操作非常有用. 列子: Sql代码 update tb_User tb_User usr inner join tb_Address addr on usr.nAddressFK = addr.nAddressID tb_User tb_User usr update的格式是 update t1 set t1.name=’Liu’ from t1 inner join t2 on t1.id = t2.tid MYSQL，ACCESS 写法如下: Sql代码 UPDATE mem_world AS mw1 INNER JOIN mem_world AS mw2 ON mw1.parentid = mw2.wid mw2.baseid mw2.parentid mw2.size > 1; mw2.mw2.parentid mw2.size > 1; on是表连接的筛选条件就是说，表连接后，会产生一个类似于临时的视图这么一个东西 where是从这个临时的视图中筛选数据的所以，虚拟主机，服务器空间，你首先要搞清，网站空间，你的所谓的2个条件属于哪一种 Delete delete 语句也是类似 t2 on t1.id = t2.tid 注意蓝色部分。 mysql: Sql代码 DELETE mwb FROM mem_world_building AS mwb INNER JOIN mem_world AS mw ON mwb.wid = mw.wid baseid mw.parentid mw.size > 1; baseid mw.parentid mw.size > 1; 下面是ORACLE的: Sql代码 DELETE TABLE1 where KHID exists ( select KHID from table2 where FWDWID=8) Sql代码 table2

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