表 A
ID NAME PRICE DATE
1 aaa 500 2009-01-02
2 aaa 550 2009-02-02
3 aaa 480 2009-02-05
4 bbb 800 2008-12-01
5 bbb 860 2009-02-01
6 ccc 900 2009-02-05
7 ddd 1200 2009-01-01
8 ddd 1500 2009-03-08
想实现
1.取每个类别的Name的最新的日期的记录
2. 取每个类别Name 的临近的上期记录 进行比较。 当前的记录跟上期记录的价格 是升了还是降了
结果如下:
NAME PRICE DATE
aaa 480 2009-02-05 下降70
bbb 860 2009-02-01 上涨60
ccc 900 2009-02-05 无
ddd 1500 2009-03-08 上涨300
请问如何通过语句实现 谢谢
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declare @t table(ID int, NAME varchar(10), PRICE int,DATE datetime)
insert @t select 1,'aaa',500,'2009-1-2'
insert @t select 2,'aaa',550,'2009-2-2'
insert @t select 3,'aaa',480,'2009-2-5'
insert @t select 4,'bbb',800,'2008-12-1'
insert @t select 5,'bbb',860,'2009-2-1'
insert @t select 6,'ccc',900,'2009-2-5'
insert @t select 7,'ddd',1200,'2009-1-1'
insert @t select 8,'ddd',1500,'2009-3-8'
select a.NAME,a.PRICE,a.DATE,价格变化=case when a.price-b.price<0 then '下降'+ltrim(abs(a.price-b.price)) when a.price-b.price=0 then '无' else '上涨'+ltrim(abs(a.price-b.price)) end
from
(select * from @t t where id =(select top 1 id from @t where name=t.name order by date desc)) a
join
(select * from @t t where id =(select top 1 id from (select top 2 * from @t where name=t.name order by date desc) t1 where t1.name=t.name order by date)) b
on a.name=b.name
价格上涨下降
最新推荐文章于 2023-05-02 23:07:00 发布