create table t1(a int,b int,c int);
create table t2(d int,b int,e int);
insert into t1 values(1,2,3);
insert into t1 values(2,3,4);
insert into t1 values(3,4,5);
insert into t2 values(3,2,5);
insert into t2 values(4,2,1);
insert into t2 values(6,3,8);
select distinct a from t1,t2 where e in (5,1);