QUERY PLAN
GroupAggregate (cost=53.96..54.07 rows=6 width=12)
Group Key: parent_id
-> Sort (cost=53.96..53.97 rows=7 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..53.86 rows=7 width=4)
Filter: ((status = 1) AND (parent_id = ANY ('{1596,1734,1768,1769}'::integer[])))