sql server 2005 中的分區函數用法(partition by 字段)

以下例子根據Item 分組後.排序.

應用例子如下:

if exists(select 1 from sys.objects where object_id=object_id('tab'))
begin
    drop table tab
end
go
create table tab(item int, date datetime, temp int)
insert tab select 10,'2006-01-01',0
union all select 10,'2006-02-01',0
union all select 10,'2006-03-01',0
union all select 20,'2006-01-01',0
union all select 20,'2006-02-01',0
union all select 30,'2006-01-01',0
union all select 30,'2006-02-01',0
union all select 30,'2006-03-01',0
union all select 30,'2006-04-01',0
union all select 30,'2006-05-01',0
go
select *,row_number() over(partition by item order by date  ) as t from tab
go

--結果
/**//*
item        date                    temp        t
----------- ----------------------- ----------- --------------------
10          2006-01-01 00:00:00.000 0           1
10          2006-02-01 00:00:00.000 0           2
10          2006-03-01 00:00:00.000 0           3
20          2006-01-01 00:00:00.000 0           1
20          2006-02-01 00:00:00.000 0           2
30          2006-01-01 00:00:00.000 0           1
30          2006-02-01 00:00:00.000 0           2
30          2006-03-01 00:00:00.000 0           3
30          2006-04-01 00:00:00.000 0           4
30          2006-05-01 00:00:00.000 0           5

(10 行受影響)

*/