a表 b表 c表 ，a表和b表条件关联gid ,b表和c表关联cid，我要怎么把这3个表联表呀？
条件是gid=20
数据库类型：mysql
回复讨论(解决方案)
select * from b left join(a,c) on (a.gid=b.gid and c.cid=b.cid) where b.gid=20
如果不想要可能出现的 NULL，则
select * from a,b,c where a.gid=b.gid and b.cid=c.cid and a,gid=20
你安装一个Navicat，建立一个视图，完全不需要手写了。 直接拖就行。
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