在SQL server 2000 中怎么处理

[wzx2275067]

有三个表
表1：
ID Name Counts...
1 AAA
2 BBB
....

表2：
ID Name ....
1 AAA
2 AAA
...

表3：
ID Name ....
1 BBB
2 BBB
...

现在想把表2和3中等于AAA和BBB的总数count放入到表1的Counts中，该怎么做？
换句话就是表1中的counts就是记录表2和表3的相应统计数。

[cloudchen]

select (select count(*) from 表2 where name = 'AAA')+(select count(*) from 表3 where name = 'BBB')

[wzx2275067]

需要实时更新

[txlicenhe]

select *,
(case [name] 'AAA' then (select count(*) from 表2 where [name] = 'AAA') when 'BBB' then (select count(*) from 表3 where [name] = 'BBB') else 0 end)
as counts
from 表1

[lakeofbeer]

对表1，表2做一个触发器

[lakeofbeer]

txlicenhe(马可)
能否讲一下
case .....then ....when ...
的作用呢？
还没接触过。

[lakeofbeer]

txlicenhe(马可)
能否讲一下
case .....then ....when ...
的作用呢？
还没接触过。
查到了。。知道了哈。。

[hdslah]

select id,name ,(select count(*) from (select name from 表2 union all select name from 表3) b where b.name =a.name) count from 表1 a

[lakeofbeer]

定义两个变量
分别放2表和3表 AAAA 和 BBBB中 count 的和
然后 update

[victorycyz]

update table1 set counts=count(b.id) from table1 a join table2 b on a.name=b.name group by a.id

update table1 set counts=count(b.id) from table1 a join table3 b on a.name=b.name group by a.id

[victorycyz]

不过，表1其实是多余的。

[yoki]

update table1
set counts=(select count(*) from table2 where name='AAA')
where name='AAA'

update table1
set counts=(select count(*) from table2 where name='BBB')
where name='BBB'

[zjcxc]

--方法1.
update 表1 set counts=b.ab
from 表1 a join (
select name=isnull(a.name,b.name,ab=sum(isnull(aa,0)+isnull(bb,0))
from(
select name,aa=count(*) from 表2 group by name
) a full join(
select name,bb=count(*) from 表3 group by name
) b on a.name=b.name
) b on a.name=b.name

[zjcxc]

--方法2.
update 表1 set Counts=(select count(*) from
(select name from 表2 union al select name from 表3) aa where name=a.name)
from 表1 a

--方法3.
update 表1 set counts=b.ab
from 表1 a join (
select name,ab=count(*)
from(select name from 表2 union all select name from 表3) a
group by name
) b on a.name=b.name

[zjcxc]

--上面的有些地方写错了,改一下:

--方法1.
update 表1 set counts=b.ab
from 表1 a join (
select name=isnull(a.name,b.name),ab=sum(isnull(aa,0)+isnull(bb,0))
from(
select name,aa=count(*) from 表2 group by name
) a full join(
select name,bb=count(*) from 表3 group by name
) b on a.name=b.name group by isnull(a.name,b.name)
) b on a.name=b.name


--方法2.
update 表1 set Counts=(select count(*) from
(select name from 表2 union all select name from 表3) aa where name=a.name)
from 表1 a


--方法3.
update 表1 set counts=b.ab
from 表1 a join (
select name,ab=count(*)
from(select name from 表2 union all select name from 表3) a
group by name
) b on a.name=b.name

[zjcxc]

--下面是测试

--测试数据
declare @表1 table(id int,name varchar(10),counts int)
insert into @表1(id,name)
select 1,'AAA'
union all select 2,'BBB'

declare @表2 table(id int,name varchar(10))
insert into @表2
select 1,'AAA'
union all select 2,'AAA'

declare @表3 table(id int,name varchar(10))
insert into @表3
select 1,'BBB'
union all select 2,'BBB'

--方法1.
update @表1 set counts=b.ab
from @表1 a join (
select name=isnull(a.name,b.name),ab=sum(isnull(aa,0)+isnull(bb,0))
from(
select name,aa=count(*) from @表2 group by name
) a full join(
select name,bb=count(*) from @表3 group by name
) b on a.name=b.name group by isnull(a.name,b.name)
) b on a.name=b.name

--显示结果
select * from @表1

--方法2.
update @表1 set Counts=(select count(*) from
(select name from @表2 union all select name from @表3) aa where name=a.name)
from @表1 a

--显示结果
select * from @表1

--方法3.
update @表1 set counts=b.ab
from @表1 a join (
select name,ab=count(*)
from(select name from @表2 union all select name from @表3) a
group by name
) b on a.name=b.name

--显示结果
select * from @表1

/*--测试结果
--方法1
id name counts
----------- ---------- -----------
1 AAA 2
2 BBB 2

（所影响的行数为 2 行）


--方法2
id name counts
----------- ---------- -----------
1 AAA 2
2 BBB 2

（所影响的行数为 2 行）


--方法3
id name counts
----------- ---------- -----------
1 AAA 2
2 BBB 2

（所影响的行数为 2 行）
--*/

[wzx2275067]

SELECT ClassID,ClassName,
{case Belong '0' then SELECT COUNT(StuScore2002.ClassID) AS Amount
FROM Class INNER JOIN
StuScore2002 ON Class.ClassID = StuScore2002.ClassID
GROUP BY StuScore2002.ClassID, Class.ClassName
when '1' then SELECT COUNT(NewStu.ClassName) AS Amount
FROM Class INNER JOIN
NewStu ON Class.ClassName = NewStu.ClassName
GROUP BY NewStu.ClassName, Class.ClassName
end
}
as counts
FROM Class


这个有什么错误？