Zip parallell arrays in hive - hive

Question

I have parallel arrays in a hive table, like this:
with tbl as ( select array(1,2,3) as x, array('a','b','c') as y)
select x,y from tbl;
x y
[1,2,3] ["a","b","c"]
1 row selected (0.108 seconds)
How can I zip them together (like the python zip function), so that I get back a list of structs, like
[(1, "a"), (2, "b"), (3,"c")]

Answer 1

You can posexplode so it gives the positions in the array which can then be used for filtering.
select x,y,collect_list(struct(val1,val2))
from tbl
lateral view posexplode(x) t1 as p1,val1
lateral view posexplode(y) t2 as p2,val2
where p1=p2
group by x,y

Answer 2

Here was my attempt at avoiding a double-explode:
with tbl as (select array(1,2,3,4,5) as x, array('a','b','c','d','e') as y)
select collect_list(struct(xi, y[i-1]))
from tbl lateral view posexplode(x) tbl2 as xi, i;
However, I ran into a strange error:
Error: Error while compiling statement: FAILED: IllegalArgumentException Size requested for unknown type: java.util.Collection (state=42000,code=40000)
I was able to work around it using
set hive.execution.engine=mr;
which is not as fast / optimized as using spark or tez as the back end.