explain.depesz.com

PostgreSQL's explain analyze made readable

Result: oj6q

Settings
# exclusive inclusive rows x rows loops node
1. 0.038 576.700 ↑ 28.8 16 1

Merge Left Join (cost=60,459.03..60,462.72 rows=460 width=180) (actual time=576.674..576.700 rows=16 loops=1)

  • Merge Cond: (node.id = s.locationid)
2. 0.007 0.016 ↑ 28.8 16 1

Sort (cost=34.94..36.09 rows=460 width=148) (actual time=0.014..0.016 rows=16 loops=1)

  • Sort Key: node.id
  • Sort Method: quicksort Memory: 27kB
3. 0.009 0.009 ↑ 28.8 16 1

Seq Scan on node (cost=0.00..14.60 rows=460 width=148) (actual time=0.007..0.009 rows=16 loops=1)

4. 0.006 576.646 ↑ 1.0 16 1

Sort (cost=60,424.09..60,424.13 rows=16 width=12) (actual time=576.645..576.646 rows=16 loops=1)

  • Sort Key: s.locationid
  • Sort Method: quicksort Memory: 25kB
5. 0.003 576.640 ↑ 1.0 16 1

Subquery Scan on s (cost=60,423.45..60,423.77 rows=16 width=12) (actual time=576.634..576.640 rows=16 loops=1)

6. 0.012 576.637 ↑ 1.0 16 1

HashAggregate (cost=60,423.45..60,423.61 rows=16 width=12) (actual time=576.634..576.637 rows=16 loops=1)

  • Group Key: bluetooth.locationid, (max(bluetooth.uploadts))
7. 0.004 576.625 ↑ 1.0 16 1

Append (cost=59,153.85..60,423.37 rows=16 width=12) (actual time=558.154..576.625 rows=16 loops=1)

8. 0.000 558.184 ↑ 1.0 13 1

Finalize GroupAggregate (cost=59,153.85..59,157.14 rows=13 width=12) (actual time=558.154..558.184 rows=13 loops=1)

  • Group Key: bluetooth.locationid
9. 0.000 558.213 ↓ 1.5 39 1

Gather Merge (cost=59,153.85..59,156.88 rows=26 width=12) (actual time=558.147..558.213 rows=39 loops=1)

  • Workers Planned: 2
  • Workers Launched: 2
10. 0.054 1,668.255 ↑ 1.0 13 3

Sort (cost=58,153.83..58,153.86 rows=13 width=12) (actual time=556.084..556.085 rows=13 loops=3)

  • Sort Key: bluetooth.locationid
  • Sort Method: quicksort Memory: 25kB
  • Worker 0: Sort Method: quicksort Memory: 25kB
  • Worker 1: Sort Method: quicksort Memory: 25kB
11. 1,248.768 1,668.201 ↑ 1.0 13 3

Partial HashAggregate (cost=58,153.46..58,153.59 rows=13 width=12) (actual time=556.065..556.067 rows=13 loops=3)

  • Group Key: bluetooth.locationid
12. 419.433 419.433 ↑ 1.2 1,535,549 3

Parallel Seq Scan on bluetooth (cost=0.00..48,556.97 rows=1,919,297 width=12) (actual time=0.013..139.811 rows=1,535,549 loops=3)

13. 13.824 18.437 ↑ 1.0 3 1

HashAggregate (cost=1,265.96..1,265.99 rows=3 width=12) (actual time=18.437..18.437 rows=3 loops=1)

  • Group Key: pollution.locationid
14. 4.613 4.613 ↑ 1.0 51,966 1

Seq Scan on pollution (cost=0.00..1,005.97 rows=51,997 width=12) (actual time=0.010..4.613 rows=51,966 loops=1)

Planning time : 0.179 ms
Execution time : 576.813 ms