在线等，SQL问题，谢谢。

[bjseaman]

表A

id username password
1 user1 12345
2 user2 12345
3 user3 12345

表B
id userid
1 1
2 3

把表A中id与表B中userid相同的输出，输出内容是表A的username值
例如现在表B中userid有1和3，输出结果应该是表A的user1和user3
如何写SQL?
谢谢

[reaperwu]

select * from A inner join B on A.id = B.id

[TrueAndFalse]

select a.username from A a,B b where a.id=b.userid

[tuoshi]

select a.username from 表A a,表B b where a.id=b.userid

[reaperwu]

错了
select * from A inner join B on A.id = B.userid

[tuoshi]

又慢了一步！~~

[cdsh123]

select * from A inner join B on A.id = B.userid

[reaperwu]

select A.* from A inner join B on A.id = B.userid
也可以用
select A.* from A left outer join B on A.id = B.userid