QUERY PLAN
GroupAggregate (cost=60.76..60.92 rows=8 width=12)
Group Key: parent_id
-> Sort (cost=60.76..60.79 rows=10 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..60.60 rows=10 width=4)
Filter: (parent_id = ANY ('{1576,1566,1562,1561,1560,1559,1558,1557,1509,1456}'::integer[]))