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发表于 2011-10-30 08:39:25
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Re:今天面试碰到了一个SQL题目,不知道怎么
SQL code 取n到m行
1.
select top (n-m+1) * from tablename where id not in (select top n id from tablename order by id asc/*|desc*/)
2.
select top m * into 临时表(或表变量) from tablename order by columnname -- 将top m笔插入到临时表
set rowcount n --只取n条结果
select * from 表变量 order by columnname desc
3.
select top n * from
(select top m * from tablename order by columnname) a
order by columnname desc
4.如果tablename里没有其他identity列,那么:
先生成一个序列,存储在一临时表中.
select identity(int) id0,* into #temp from tablename
取n到m条的语句为:
select * from #temp where id0 > =n and id0 <= m
如果你在执行select identity(int) id0,* into #temp from tablename这条语句的时候报错,那是因为你的DB中间的select into/bulkcopy属性没有打开要先执行:
exec sp_dboption 你的DB名字,'select into/bulkcopy',true
5.如果表里有identity属性,那么简单:
select * from tablename where identity_col between n and m
6.SQL2005开始.可以使用row_number() over()生成行号
;with cte as
(
select id0=row_number() over(order by id),* from tablename
)
select * from cte where id0 between n to m |
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