结合其它表来查询的查询语句
表A的结构

id bxgsid
1 2
2 2
3 1
4 3

表B的结构

id aid

1 1
2 3
3 2
4 2

其中B.aid 和 A.id 是对应的
现在想用一句SQL语句，查询表B中，A.bxgsid=2的数据， 即结果应该为B.1 B.3 B.4

请指教，我现在写的是

select * from b where(select * from a where bxgsid=2)
但通不过，
[解决办法]

select B.* from A,B where A.ID=B.ID and A.bxgsid=2

[解决办法]
select * from b where sid in (select id from a where bxgsid=2)
[解决办法]

----------------------------
-- Author  :TravyLee(物是人非事事休,欲语泪先流!)
-- Date    :2012-11-28 09:09:40
-- Version:

--      Microsoft SQL Server 2012 - 11.0.2100.60 (Intel X86) 

--Feb 10 2012 19:13:17 

--Copyright (c) Microsoft Corporation

--Enterprise Edition: Core-based Licensing on Windows NT 6.1 <X86> (Build 7601: Service Pack 1)

--
----------------------------
--> 测试数据：[A]
if object_id('[A]') is not null drop table [A]
go 
create table [A]([id] int,[bxgsid] int)
insert [A]
select 1,2 union all
select 2,2 union all
select 3,1 union all
select 4,3
--> 测试数据：[B]
if object_id('[B]') is not null drop table [B]
go 
create table [B]([id] int,[aid] int)
insert [B]
select 1,1 union all
select 2,3 union all
select 3,2 union all
select 4,2
go

select
b.*
from
B
inner join
A
on a.id=b.aid
where
a.bxgsid=2
/*
idaid
----------------
11
32
42
*/