QUERY PLAN
GroupAggregate (cost=53.76..53.86 rows=5 width=12)
Group Key: parent_id
-> Sort (cost=53.76..53.78 rows=6 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..53.68 rows=6 width=4)
Filter: (parent_id = ANY ('{1734,1735,1746,1751,1754,1772}'::integer[]))