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hackingwu
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select * from A select c in (select c from B) limit 10; 数据库会把 c 全部查出来吗

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  •   hackingwu ·
    hackingwu · May 14, 2020 · 2073 views
    This topic created in 2376 days ago, the information mentioned may be changed or developed.

    select * from A select c in (select c from B) limit 10; 数据库会把 c 全部查出来吗? 不考虑 join on 的写法,纯粹请教 subquery 里的 select c from B 会查询 B 表中全量数据的 c ?

    4 replies  •  2020-05-15 09:05:43 +08:00
    jay0726
    jay0726
    May 14, 2020
    1
    看不懂你在说什么
    qiayue
    qiayue
    May 14, 2020
    2
    explain 自己看看分析结果就知道
    hackingwu
    hackingwu
    OP
    May 14, 2020
    3
    @qiayue 来问问题前已经 explain 过了,没有看出来。
    UnknownR
    UnknownR
    May 15, 2020
    4
    select * from B.c.A ?
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