drop table if exists t1,t2;
create table t1 (id int(10) not null unique);
create table t2 (id int(10) not null primary key,
val int(10) not null);
insert into t1 values (1),(2),(4);
insert into t2 values (1,1),(2,1),(3,1),(4,2);
select one.id, elt(two.val,'one','two') from t1 one, t2 two where two.id=one.id order by one.id;
id	elt(two.val,'one','two')
1	one
2	one
4	two
drop table t1,t2;