explain.depesz.com

PostgreSQL's explain analyze made readable

Result: t7AI

Settings
# exclusive inclusive rows x rows loops node
1. 0.372 73,982.815 ↓ 2,001.0 2,001 1

Subquery Scan on tm (cost=1,475,705.79..1,475,705.80 rows=1 width=89) (actual time=73,317.783..73,982.815 rows=2,001 loops=1)

2. 664.427 73,982.443 ↓ 2,001.0 2,001 1

Limit (cost=1,475,705.79..1,475,705.79 rows=1 width=89) (actual time=73,317.781..73,982.443 rows=2,001 loops=1)

3. 0.000 73,318.016 ↓ 2,001.0 2,001 1

Sort (cost=1,475,705.79..1,475,705.79 rows=1 width=89) (actual time=73,317.780..73,318.016 rows=2,001 loops=1)

  • Sort Key: m.start_time DESC
  • Sort Method: quicksort Memory: 641kB
4. 834.635 73,980.597 ↓ 3,744.0 3,744 1

Gather (cost=1,273,340.61..1,475,705.78 rows=1 width=89) (actual time=70,242.342..73,980.597 rows=3,744 loops=1)

  • Workers Planned: 5
  • Workers Launched: 5
5. 2.558 73,145.962 ↓ 624.0 624 6

Nested Loop (cost=1,272,340.61..1,474,705.68 rows=1 width=89) (actual time=69,949.430..73,145.962 rows=624 loops=6)

  • Join Filter: (m.measurement_id = measurements.measurement_id)
6. 4,115.633 73,143.400 ↓ 20.8 624 6

Parallel Hash Semi Join (cost=1,272,340.18..1,474,610.87 rows=30 width=93) (actual time=69,949.372..73,143.400 rows=624 loops=6)

  • Hash Cond: (m.measurement_id = measurement_files.measurement_id)
7. 8,318.514 8,318.514 ↑ 1.3 624 6

Parallel Seq Scan on measurements m (cost=0.00..175,290.21 rows=817 width=89) (actual time=4,022.536..8,318.514 rows=624 loops=6)

  • Filter: ((start_time > '2018-12-03 00:00:00'::timestamp without time zone) AND (start_time < '2018-12-04 00:00:00'::timestamp without time zone))
  • Rows Removed by Filter: 1585832
8. 1,759.418 60,709.253 ↓ 1.2 8,050,006 6

Parallel Hash (cost=1,159,136.12..1,159,136.12 rows=6,900,005 width=4) (actual time=60,709.253..60,709.253 rows=8,050,006 loops=6)

  • Buckets: 4194304 Batches: 32 Memory Usage: 92096kB
9. 58,949.835 58,949.835 ↓ 1.2 8,050,006 6

Parallel Seq Scan on measurement_files (cost=0.00..1,159,136.12 rows=6,900,005 width=4) (actual time=14.354..58,949.835 rows=8,050,006 loops=6)

  • Filter: (mount_point_id = ANY ('{1,2,3,4,5,6,7,8,9,10}'::integer[]))
10. 0.004 0.004 ↑ 1.0 1 3,744

Index Scan using pkey_measurements on measurements (cost=0.43..3.15 rows=1 width=4) (actual time=0.004..0.004 rows=1 loops=3,744)

  • Index Cond: (measurement_id = measurement_files.measurement_id)
  • Filter: ((start_time > '2018-12-03 00:00:00'::timestamp without time zone) AND (start_time < '2018-12-04 00:00:00'::timestamp without time zone))