heat
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如何实现多个表的 JOIN 联合查询

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  •   heat · Mar 14, 2015 · 3622 views
    This topic created in 4252 days ago, the information mentioned may be changed or developed.
    目前有3个表 A B C

    需求是先A和B内联查询出一个结果,然后左联C表(C数据是不全的)

    我的写法是

    SELECT * FROM A,B LEFT JOIN C ON A.id=C.id WHERE A.id=B.id ORDER BY id

    虽然没有报错,但是结果是不对的。。。

    请问我该怎么写语句才能查出正确的结果
    2 replies  •  2015-03-14 11:07:03 +08:00
    owei
    owei
    Mar 14, 2015
    1
    select * from (select * from a inner b on a.id=b.id) left join c on a.id= c.id
    heat
    heat
    OP
    Mar 14, 2015
    2
    @owei 刚发出来就解决了,我用的方法是

    SELECT * FROM A LEFT JOIN C ON A.id=C.id INNER JOIN B ON B.id=A.id
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