QUERY PLAN
GroupAggregate (cost=47.85..47.91 rows=3 width=12)
Group Key: parent_id
-> Sort (cost=47.85..47.86 rows=3 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..47.83 rows=3 width=4)
Filter: (parent_id = ANY ('{1664,1658,1666}'::integer[]))