QUERY PLAN
GroupAggregate (cost=57.99..58.18 rows=9 width=12)
Group Key: parent_id
-> Sort (cost=57.99..58.03 rows=13 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..57.75 rows=13 width=4)
Filter: (parent_id = ANY ('{1596,1641,1647,1347,1358,1359,1349,1350,1357,1356}'::integer[]))