QUERY PLAN
GroupAggregate (cost=59.58..59.74 rows=9 width=12)
Group Key: parent_id
-> Sort (cost=59.58..59.60 rows=10 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..59.41 rows=10 width=4)
Filter: (parent_id = ANY ('{1576,1577,1578,1596,1668,1686,1734,1745,1768}'::integer[]))