QUERY PLAN
GroupAggregate (cost=51.45..51.56 rows=6 width=12)
Group Key: parent_id
-> Sort (cost=51.45..51.47 rows=7 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..51.35 rows=7 width=4)
Filter: (parent_id = ANY ('{1731,1713,1712,1711}'::integer[]))