QUERY PLAN
GroupAggregate (cost=61.22..61.39 rows=9 width=12)
Group Key: parent_id
-> Sort (cost=61.22..61.24 rows=11 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..61.02 rows=11 width=4)
Filter: (parent_id = ANY ('{346,347,355,413,796,850,1535,1536,1537,1550}'::integer[]))