QUERY PLAN
GroupAggregate (cost=76.46..76.76 rows=15 width=12)
Group Key: parent_id
-> Sort (cost=76.46..76.51 rows=20 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..76.03 rows=20 width=4)
Filter: (parent_id = ANY ('{9,17,23,10,34,12,11,52,15,58,62,57,63,61,54,48,74,76,75,71}'::integer[]))