QUERY PLAN
GroupAggregate (cost=51.09..51.14 rows=3 width=12)
Group Key: parent_id
-> Sort (cost=51.09..51.10 rows=3 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..51.06 rows=3 width=4)
Filter: ((parent_id = ANY ('{1535,1667}'::integer[])) AND (status = 1))