求SQL语句

表

ID,FORID,FSUM,FDate
1  1    20  2009-01-01
2  1    30  2009-02-01
3  1    40  2009-03-01
4  2    10  2009-01-01

查询结果


ID,FORID,FSUM,FDate          ffsum
1  1    20  2009-01-01    20
2  1    30  2009-02-01    50
3  1    40  2009-03-01    90
4  2    10  2009-01-01    10

多生成一列FFsum,相同ForID,累加日期前的fsum值

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select ID,FORID,FSUM,FDate,(FSUM+iif(isnull((select sum(FSUM) from 表 where ID <t.ID)),0,(select sum(FSUM) from 表 where ID <t.ID))) as ffsum from 表 t

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SQL code:
select a.ID,a.FORID,a.FSUM,a.FDate,sum(b.FSUM) as ffsum
from 表 a ,表 b
where a.FORID=b.FORID and a.ID>=b.ID
group by a.ID,a.FORID,a.FSUM,a.FDate

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引用

select ID,FORID,FSUM,FDate,(FSUM+iif(isnull((select sum(FSUM) from 表 where ID <t.ID)),0,(select sum(FSUM) from 表 where ID <t.ID))) as ffsum from 表 t

精简一下:
select ID,FORID,FSUM,FDate,(select sum(FSUM) from 表 where ID <=t.ID) as ffsu