QUERY PLAN
GroupAggregate (cost=48.23..48.30 rows=4 width=12)
Group Key: parent_id
-> Sort (cost=48.23..48.24 rows=4 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..48.19 rows=4 width=4)
Filter: (parent_id = ANY ('{1596,1734,1768}'::integer[]))