Try to use COLLECT_LIST(col) after Hive 0.13.0
SELECT
hash_id, COLLECT_LIST(num_of_cats) AS aggr_set
FROM
tablename
WHERE
blablabla
GROUP BY
hash_id
;
Try to use COLLECT_LIST(col) after Hive 0.13.0
SELECT
hash_id, COLLECT_LIST(num_of_cats) AS aggr_set
FROM
tablename
WHERE
blablabla
GROUP BY
hash_id
;