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select t.a,t.b from t where t.c in (1, 2, 3, 4, 5) order by created_at desc;
怎么让每个 c 只返回一个结果？即最新created_at desc那个.
如果直接这样：
select t.a,t.b from t where t.c in (1, 2, 3, 4, 5) order by created_at desc limit 1;
就全部一个结果.
因为 select t.a,t.b from t where t.c = 1/2/3/4/5 每个都会返回多个结果
怎么让每个 c 只返回一个结果？即最新created_at desc那个.
如果直接这样：
select t.a,t.b from t where t.c in (1, 2, 3, 4, 5) order by created_at desc limit 1;
就全部一个结果.
因为 select t.a,t.b from t where t.c = 1/2/3/4/5 每个都会返回多个结果
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1
manhere Jan 16, 2014
既然是一个，为什么还要用in() ？
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jandan Jan 16, 2014
多个结果是否一样？若是distinct。
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4
yjsslab OP 怎么不能改帖子了？？？？
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10
sun1991 Jan 16, 2014
如果是Oracle的话, 参见row_number, partition by
http://www.java2s.com/Tutorial/Oracle/0320__Analytical-Functions/ROWNUMBERwithPartition.htm SQL Server应该有类似写法. 别的就不知道了 |
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