QUERY PLAN
Limit (cost=296.76..296.77 rows=1 width=248)
InitPlan 1 (returns $0)
-> Aggregate (cost=146.94..146.95 rows=1 width=32)
-> Seq Scan on tbl_tasks s_1 (cost=0.00..146.82 rows=44 width=13)
Filter: ((tree_path IS NOT NULL) AND (head_of = 1001))
-> Sort (cost=149.82..149.82 rows=1 width=248)
Sort Key: s.created_at DESC
-> Group (cost=149.80..149.81 rows=1 width=248)
Group Key: s.id
-> Sort (cost=149.80..149.80 rows=1 width=248)
Sort Key: s.id
-> Seq Scan on tbl_tasks s (cost=0.00..149.79 rows=1 width=248)
Filter: ((parent_id IS NULL) AND (tree_path @> $0) AND (head_of = 1001))