QUERY PLAN
GroupAggregate (cost=49.82..49.91 rows=5 width=12)
Group Key: parent_id
-> Sort (cost=49.82..49.83 rows=6 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..49.74 rows=6 width=4)
Filter: (parent_id = ANY ('{1713,1731,1712}'::integer[]))