求一sql语句，急！
表t1：c1，c2，c3，c4
1 1 a a
1 2 a c
.............

表t2：c1,c2,c3,c4
1 1 d d
2 1 a a
2 2 c c


把t1中t.c1、t.c2不等于t2.c1、t2.c2的行插入t2中，怎么写 ？
如上则把t1中的(1 2 a c)行插入到t2中。




[解决办法]
c1和c2是整数类型的?

insert into T2
select *
from T1
where C1*100000000 + C2 not in (select C1*100000000 + C2 from T2)

[解决办法]
insert into t2
select * from t1
where c2 not in(
select t1.c2 from t1,t2
where t1.c1=t2.c1 and t1.c2=t2.c2);