icerunz
V2EX  ›  问与答

求一条SQL,两表取值的,是不是要用子查询?

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  •   icerunz · Feb 15, 2012 · 3974 views
    This topic created in 5207 days ago, the information mentioned may be changed or developed.
    需求是要从table1查出id1,然后从table2中根据id1查出对应的id2。
    表的大概结构就是:
    table1的字段:
    id_ai,id1,name1,desc1
    table2的字段:
    id_ai,id1,id2

    这样的需求能够用一句SQL就搞定么?
    谢谢。
    3 replies    1970-01-01 08:00:00 +08:00
    ri0day
        1
    ri0day  
       Feb 15, 2012
    join 也可以吧
    reus
        2
    reus  
       Feb 15, 2012 via Android
    select id2 from table1 left join table2 on table1.id1=table2.id1 where ....
    这样吧
    icerunz
        3
    icerunz  
    OP
       Feb 15, 2012
    @reus 感谢,通了。:)
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