WIN2333的博客

首先来看表结构1.person表2.job表 PS: 随意建的表。。不要在意细节 先看看匹配单个列select * from person where name in (select name from job)执行结果多个列 根据name和sex一起匹配select * from person where(name,sex) in (select name,sex from job)执行结果重