多表查询求统计，求sql语句

[意识模糊]

有三个表：A,B,C
A表保存会员信息，包括ID，会员等级(1,2,3,4)等
B表保存会员购买信息(购买金额)
C表保存会员登录时间(类型datetime)
每个表都有会员的ID，求今年2月后还有登录记录并且消费大于10块各个等级会员的个数和2月后没有登录过的记录

[孤独加百列]

--今年2月后还有登录记录并且消费大于10块各个等级会员的个数
SELECT 会员等级,COUNT(1) AS num
FROM a INNER JOIN B ON A.Id = B.Id AND B.购买金额 > 10
INNER JOIN C ON A.Id = C.id AND 登录时间 > RTRIM(DATEPART(YEAR,GETDATE())) + '-03-01 0:00:00'
GROUP BY 会员等级

--2月后没有登录过的记录
SELECT ID,会员等级
FROM a 
WHERE NOT EXISTS (SELECT 1 FROM C WHERE A.Id = C.id AND 登录时间 > RTRIM(DATEPART(YEAR,GETDATE())) + '-03-01 0:00:00')

[CAD233]

SELECT 会员等级,COUNT(*) AS numFROM a,b,c
where A.Id = B.Id
and A.Id = C.id
and B.购买金额 > 10
and 登录时间 > RTRIM(DATEPART(YEAR,GETDATE())) + '-02-01 0:00:00')
GROUP BY 会员等级

[CAD233]

[Quote=引用 2 楼 的回复:]

SELECT 会员等级,COUNT(*) AS numFROM a,b,c
where A.Id = B.Id
and A.Id = C.id
and B.购买金额 > 10
and 登录时间 > RTRIM(DATEPART(YEAR,GETDATE())) + '-02-01 0:00:00')
GROUP BY 会员等级
[/Quote]
不知道有没有错，求指导，新手求帮助

[以学习为目的]

--今年2月后还有登录记录并且消费大于10块各个等级会员的个数
select  A.会员等级,
        COUNT(*)    
from  A,B,C
where A.ID=B.ID and 
      A.ID=C.ID and
      B.购买金额>'10' and
      C.登陆时间> RTRIM(DATEPART(YEAR,GETDATE())) + '-03-01 0:00:00'
GROUP BY 会员等级

--2月后没有登录过的记录


SELECT ID,登陆时间
FROM  A , C
WHERE  A.Id = C.id and
       C.登录时间 < RTRIM(DATEPART(YEAR,GETDATE())) + '-03-01 0:00:00')

[意识模糊]

[Quote=引用 1 楼 的回复:]

SQL code


--今年2月后还有登录记录并且消费大于10块各个等级会员的个数
SELECT 会员等级,COUNT(1) AS num
FROM a INNER JOIN B ON A.Id = B.Id AND B.购买金额 > 10
INNER JOIN C ON A.Id = C.id AND 登录时间 > RTRIM(DATEPART(YEAR,GETDATE())) + '-0……
[/Quote]
2月后没有登录过的记录也要统计消费超过10块的各个等级会员数量，sql怎么写，谢谢

[以学习为目的]

[Quote=引用 5 楼 的回复:]
引用 1 楼 的回复:

SQL code


--今年2月后还有登录记录并且消费大于10块各个等级会员的个数
SELECT 会员等级,COUNT(1) AS num
FROM a INNER JOIN B ON A.Id = B.Id AND B.购买金额 > 10
INNER JOIN C ON A.Id = C.id AND 登录时间 > RTRIM(DATEPART(YEA……
[/Quote]

--try
SELECT 会员等级, COUNT(*) AS NUM
FROM  A ,B, C
WHERE  A.Id = C.id and
       B.Id = C.id and
       B.消费金额>'10' and
       C.登录时间 < RTRIM(DATEPART(YEAR,GETDATE())) + '-03-01 0:00:00')
GROUP BY 会员等级

[tim_spac_126]

-- 各个等级会员的个数
select Level, count(1)
from A
left join (
  select userID
  from B
  group by userID
  -- 消费大于10
  having sum(amount)>10
) as b on a.ID = b.userID
where 1=1
-- 今年2月后还有登录记录
and exists (select 1 from C where c.userID = a.ID
    and c.logintime >= '2012-02-01')
group by Level