QUERY PLAN
GroupAggregate (cost=58.03..58.19 rows=8 width=12)
Group Key: parent_id
-> Sort (cost=58.03..58.06 rows=10 width=4)
Sort Key: parent_id
-> Seq Scan on tbl_tasks (cost=0.00..57.86 rows=10 width=4)
Filter: (parent_id = ANY ('{1596,1641,1636,1347,1358,1359,1349,1350,1357,1356}'::integer[]))