QUERY PLAN
GroupAggregate (cost=151.31..151.37 rows=3 width=12)
Group Key: parent_id
-> Sort (cost=151.31..151.32 rows=4 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..151.27 rows=4 width=4)
Filter: ((status = 1) AND (parent_id = ANY ('{1586,1585,1584}'::integer[])))