QUERY PLAN
Limit (cost=29.07..29.12 rows=20 width=109)
-> Sort (cost=29.07..30.14 rows=429 width=109)
Sort Key: d.created_at DESC
-> HashAggregate (cost=13.36..17.65 rows=429 width=109)
Group Key: d.id
-> Seq Scan on tbl_documents d (cost=0.00..12.29 rows=429 width=109)