看看高手对于这个查询如何来写，大家交流下：）

Question

要求：统计出“当日注册的用户,按照渠道分类，7日后付费总额”。例如，2008-11-1注册的用户，按照渠道分类，2008-11-7日消费总额是多少？依次类推注册表  user
userid      channel     registerDate
a                C1                2008-11-1
b                C2                2008-11-1
c                 C1               2008-11-2
d                C3               2008-11-3
e                C2                2008-11-4
f                  C2              2008-11-5
g                  C2              2008-11-6
h                  C3              2008-11-7
i                  C3              2008-11-8
j                  C2              2008-11-9订单表  order
orderdate           userid                paymoney
2008-11-01           a                       10
2008-11-01           b                       10
2008-11-02           a                       30
2008-11-03           e                       10
2008-11-04           a                       10
2008-11-05            f                       10
2008-11-06           c                       10
2008-11-07           c                       10
2008-11-08           b                       20
2008-11-09           d                       40
2008-11-10           f                       10

Answer 1

select 
  a.userid,
  a.channel,
  sum(b.paymoney)
from [user] a, [order] b
where a.userid=b.userid
and datediff(day,a.registerDate,b.orderdate)=7

Answer 2

按照你给的应该是6日后的付费总额
select 
  a.userid,
  a.channel,
  sum(b.paymoney)
from [user] a, [order] b
where a.userid=b.userid
and datediff(day,a.registerDate,b.orderdate)=6
group by a.userid,a.channel

Answer 3

只按照渠道分类
select 
  a.channel,
  sum(b.paymoney)
from [user] a, [order] b
where a.userid=b.userid
and datediff(day,a.registerDate,b.orderdate)=6
group by a.channel