QUERY PLAN
GroupAggregate (cost=50.43..50.48 rows=3 width=12)
Group Key: parent_id
-> Sort (cost=50.43..50.43 rows=3 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..50.40 rows=3 width=4)
Filter: ((status = 1) AND (parent_id = ANY ('{1596,1641,1647}'::integer[])))