QUERY PLAN
GroupAggregate (cost=57.92..58.06 rows=7 width=12)
Group Key: parent_id
-> Sort (cost=57.92..57.94 rows=10 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..57.75 rows=10 width=4)
Filter: (parent_id = ANY ('{1688,1694,1693,1692,1691,1690,1689,1651,1650,1648}'::integer[]))