QUERY PLAN
GroupAggregate (cost=174.43..174.67 rows=9 width=12)
Group Key: parent_id
-> Sort (cost=174.43..174.48 rows=20 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..174.00 rows=20 width=4)
Filter: (parent_id = ANY ('{851,783,875,893,876,863,859,852,782,871,919,909,947,1006,991,989,926,901,891,890}'::integer[]))