srcData--复杂查询得到的数据，所以不要说下面数据结构不合理

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id ProductId	StockNum	EnterTime				enterNum

12	100003		22			2014-04-28 00:00:00		10

23	100003		22			2014-04-27 00:00:00		5

41	100003		22			2014-04-25 00:00:00		18

56	100003		22			2014-04-21 00:00:00		10

64	100003		22			2014-04-19 00:00:00		8

75	100003		22			2014-04-13 00:00:00		10

97	100003		22			2014-04-07 00:00:00		5

132	100006		45			2014-05-02 00:00:00		20

163	100006		45			2014-04-28 00:00:00		15

231	100006		45			2014-04-24 00:00:00		5

468	100006		45			2014-04-23 00:00:00		5

532	100006		45			2014-04-20 00:00:00		10

562	100006		45			2014-04-19 00:00:00		15

644	100006		45			2014-04-16 00:00:00		10

687	100006		45			2014-04-15 00:00:00		5

763	100008		12			2014-04-17 00:00:00		5

796	100008		12			2014-04-15 00:00:00		10

803	100008		12			2014-04-15 00:00:00		5

825	100008		12			2014-04-11 00:00:00		15

846	100008		12			2014-04-09 00:00:00		10

867	100008		12			2014-04-02 00:00:00		5



--需要得到的数据

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id	ProductId	StockNum	EnterTime				enterNum

12	100003		22			2014-04-28 00:00:00		10

23	100003		22			2014-04-27 00:00:00		5

41	100003		22			2014-04-25 00:00:00		18

132	100006		45			2014-05-02 00:00:00		20

163	100006		45			2014-04-28 00:00:00		15

231	100006		45			2014-04-24 00:00:00		5

458	100006		45			2014-04-23 00:00:00		5

763	100008		12			2014-04-17 00:00:00		5

796	100008		12			2014-04-15 00:00:00		10



--规则是，根据ProductId分组，按时间降序排列，依次累加入库数量，

--如果达到或超出库存数量，则停止，丢掉之后的数据，开始查找下一个分组

--求高手赐教

with a(id,ProductId,StockNum,EnterTime,enterNum)as(

select 12,100003,22,'2014-04-28 00:00:00',10 union

select 23,100003,22,'2014-04-27 00:00:00',5 union

select 41,100003,22,'2014-04-25 00:00:00',18 union

select 56,100003,22,'2014-04-21 00:00:00',10 union

select 64,100003,22,'2014-04-19 00:00:00',8 union

select 75,100003,22,'2014-04-13 00:00:00',10 union

select 97,100003,22,'2014-04-07 00:00:00',5 union

select 132,100006,45,'2014-05-02 00:00:00',20 union

select 163,100006,45,'2014-04-28 00:00:00',15 union

select 231,100006,45,'2014-04-24 00:00:00',5 union

select 468,100006,45,'2014-04-23 00:00:00',5 union

select 532,100006,45,'2014-04-20 00:00:00',10 union

select 562,100006,45,'2014-04-19 00:00:00',15 union

select 644,100006,45,'2014-04-16 00:00:00',10 union

select 687,100006,45,'2014-04-15 00:00:00',5 union

select 763,100008,12,'2014-04-17 00:00:00',5 union

select 796,100008,12,'2014-04-15 00:00:00',10 union 

select 803,100008,12,'2014-04-15 00:00:00',5 union

select 825,100008,12,'2014-04-11 00:00:00',15 union

select 846,100008,12,'2014-04-09 00:00:00',10 union

select 867,100008,12,'2014-04-02 00:00:00',5)

, b as(

select *

,(select SUM(enternum) from a where b.ProductId=ProductId an