日期:2014-05-19  浏览次数:20485 次

求sql语句!
名称         数值1 数值2
a 84         100
a 140         157
a 156         168
b 218.72 225
b 266.58 276
b 284.72 291
c 4 6
c 7 9
c 8 10

查询同一名称中,上一行数值2列大于下一行数值1列的数据
得出结果如下:
a 140         157
c 7 9

------解决方案--------------------
需要用到标识列来标识上下行

create table #t(名称 char(1),数值1 numeric(20,6),数值2 numeric(20,6))
insert into #t
select 'a ',84,100
union all select 'a ',140,157
union all select 'a ',156,168
union all select 'b ',218.72,225
union all select 'b ',266.58,276
union all select 'b ',284.72,291
union all select 'c ',4,6
union all select 'c ',7,9
union all select 'c ',8,10

alter table #t add id int identity(1,1)
select 名称,数值1,数值2 from #t
where exists(select 1 from #t t where #t.名称=t.名称 and #t.id <t.id and #t.数值2> t.数值1)
/*
名称 数值1 数值2
---- ---------------------- ----------------------
a 140.000000 157.000000
c 7.000000 9.000000

(所影响的行数为 2 行)
*/
drop table #t
------解决方案--------------------
select 数值2 from 表 as T
where id > (select min(id) from 表 where 名称=T.名称) and 数值2> 数值1
------解决方案--------------------
create table t(tname char(1),num1 numeric(20,6),num2 numeric(20,6))
insert into t
select 'a ',84,100
union all select 'a ',140,157
union all select 'a ',156,168
union all select 'b ',218.72,225
union all select 'b ',266.58,276
union all select 'b ',284.72,291
union all select 'c ',4,6
union all select 'c ',7,9
union all select 'c ',8,10


select identity(int,1,1)as tid,t.* into tb from t
select a.tname,a.num1,a.num2 from tb a join tb b on a.tname=b.tname
where a.tid <b.tid and a.num2> b.num1