QUERY PLAN
GroupAggregate (cost=49.78..49.85 rows=4 width=12)
Group Key: parent_id
-> Sort (cost=49.78..49.79 rows=4 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..49.74 rows=4 width=4)
Filter: (parent_id = ANY ('{1596,1734,1768}'::integer[]))