案例表如下
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Id Type UserId Title Price Date
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1 0 1 AAA 5 2007-05-11
2 1 1 hBBB 5 2007-05-10
3 1 1 3AAA 6 2007-05-10
4 0 4 4AAA 6 2007-05-09
5 1 4 dAAA 3.5 2007-05-09
6 1 3 fAAA 7 2007-05-09
7 1 2 gAAA 9 2007-05-09
8 0 4 sAAA 10 2007-05-09
9 1 5 aAAA 8.5 2007-05-09
10 1 6 aAAA 7 2007-05-09
11 1 2 gAAA 9 2007-05-09
12 0 4 sAAA 10 2007-05-09
13 1 5 aAAA 8.5 2007-05-09
13 1 6 aAAA 7 2007-05-09
还有更多。。
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我需要对这个表进行分页,每页20条数据,分页解决了,问题就是要求每条数据的UserId是唯一的,每页每个UserId的信息只能出现一次,请问该怎么做?
-------------------------------------------------------
Id Type UserId Title Price Date
----------------------------------------------------
1 0 1 AAA 5 2007-05-11
2 1 1 hBBB 5 2007-05-10
3 1 1 3AAA 6 2007-05-10
4 0 4 4AAA 6 2007-05-09
5 1 4 dAAA 3.5 2007-05-09
6 1 3 fAAA 7 2007-05-09
7 1 2 gAAA 9 2007-05-09
8 0 4 sAAA 10 2007-05-09
9 1 5 aAAA 8.5 2007-05-09
10 1 6 aAAA 7 2007-05-09
11 1 2 gAAA 9 2007-05-09
12 0 4 sAAA 10 2007-05-09
13 1 5 aAAA 8.5 2007-05-09
13 1 6 aAAA 7 2007-05-09
还有更多。。
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我需要对这个表进行分页,每页20条数据,分页解决了,问题就是要求每条数据的UserId是唯一的,每页每个UserId的信息只能出现一次,请问该怎么做?
如果是把重复的记录删除出去用distinct就可以了
select distinct usid from table
如果单单是对重复的记录删除的话
select distinct userid from TableName
怎么用distinct ?