author:zfive5(zhaozidong)
email:zfive5@yahoo.com.cn
不说只看
a or b
select a.AId,b.BId from U1A a left join U1B b on a.AId=b.BId
union
select a.AId,b.BId from U1A a right join U1B b on a.AId=b.BId
a or b
select a.AId,b.BId from U1A a full join U1B b on a.AId=b.BId
a and b
select a.AId,b.BId from U1A a inner join U1B b on a.AId=b.BId
a
select a.AId,b.BId from U1A a left join U1B b on a.AId=b.BId
b
select a.AId,b.BId from U1A a right join U1B b on a.AId=b.BId
a*b
select a.AId,b.BId from U1A a right join U1B b on a.AId=b.BId
OK!
博客展示了SQL中不同表连接查询的示例,包括左连接、右连接、全连接、内连接等,通过具体的SQL语句呈现了不同连接方式下从U1A和U1B表中选取AId和BId字段的操作。

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