求一个自连接的SQl语句

问题描述：

我有一张表
id username provance fortes
1 tt sc m
2 rr sc d
3 cc fj m
能够查询出与tt具有相同provance和fortes的人！！
谢谢了！！

问题解答：

select b.id,b.username,b.provance,b.fortes from table_3 a
join table_3 b on ((b.provance=a.provance or b.fortes=a.fortes )and a.username='tt')

结果:
id username provance fortes
----------- ---------- ---------- ----------
1 tt sc m
2 rr sc d
3 cc fj m

(3 行受影响)

或者:
select * from table_3
where (provance in (select provance from table_3 where username='tt'))
or (fortes in (select fortes from table_3 where username='tt'))

同样:
id username provance fortes
----------- ---------- ---------- ----------
1 tt sc m
2 rr sc d
3 cc fj m

(3 行受影响)