QUERY PLAN
Aggregate (cost=293.69..293.70 rows=1 width=8)
-> Group (cost=293.67..293.68 rows=1 width=224)
Group Key: s.id
InitPlan 1 (returns $0)
-> Aggregate (cost=146.83..146.84 rows=1 width=32)
-> Seq Scan on tbl_tasks s_1 (cost=0.00..143.86 rows=1186 width=13)
Filter: (tree_path IS NOT NULL)
-> Sort (cost=146.83..146.84 rows=1 width=4)
Sort Key: s.id
-> Seq Scan on tbl_tasks s (cost=0.00..146.82 rows=1 width=4)
Filter: ((parent_id IS NULL) AND (tree_path @> $0))