QUERY PLAN
GroupAggregate (cost=159.17..159.31 rows=7 width=12)
Group Key: parent_id
-> Sort (cost=159.17..159.19 rows=10 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..159.00 rows=10 width=4)
Filter: (parent_id = ANY ('{1171,1170,1175,1176,1183,1179,1172,1167,1166,1165}'::integer[]))