How do I cross-join a table with a list?

Question

If I have a table mytable and a list

set vals = (1,2,3,4);

and I want to cross-join the table with the list (getting a new table which has 4 time as many rows as the original table and an extra val column), do I have a better option than creating an explicit temp table?

What I can do is:

select a.*, b.val
from mytable a cross join
(select stack(4,1,2,3,4) as (val) from 
 (select * from mytable limit 1) z) b;

EDIT: My main use case would be passing -hiveconf vals='4,1,2,3,4' to hive and replacing stack(4,1,2,3,4) with stack(${hiveconf:vals}) in the above code.

Answer 1

select a.*, b.val
from a lateral view explode(array(1,2,3,4)) b as val;

Answer 2

I dont know this will help.

SELECT *
from mytable cross join
(select 1 as p
union 
select 2 
union 
select 3
union 
select 4) as x