explain.depesz.com

PostgreSQL's explain analyze made readable

Result: nZ2

Settings
# exclusive inclusive rows x rows loops node
1. 348.328 11,122.461 ↑ 1.5 390,912 1

Sort (cost=2,041,547.05..2,042,980.58 rows=573,414 width=167) (actual time=11,067.242..11,122.461 rows=390,912 loops=1)

  • Sort Key: signal."timestamp
  • Sort Method: external sort Disk: 47040kB
2. 250.389 10,774.133 ↑ 1.5 390,912 1

GroupAggregate (cost=1,918,159.22..1,939,662.24 rows=573,414 width=167) (actual time=10,388.653..10,774.133 rows=390,912 loops=1)

  • Group Key: signal.signal_id, parameter.name, parameter.unit, source_type.name, source.name, source.serial, site.name, quality.method, quality.flag
3. 450.180 10,523.744 ↑ 1.5 390,912 1

Sort (cost=1,918,159.22..1,919,592.75 rows=573,414 width=167) (actual time=10,388.643..10,523.744 rows=390,912 loops=1)

  • Sort Key: signal.signal_id, parameter.name, parameter.unit, source_type.name, source.name, source.serial, site.name, quality.method, quality.flag
  • Sort Method: external merge Disk: 44592kB
4. 59.019 10,073.564 ↑ 1.5 390,912 1

Hash Left Join (cost=1,658,732.63..1,816,274.41 rows=573,414 width=167) (actual time=8,501.626..10,073.564 rows=390,912 loops=1)

  • Hash Cond: (signal_quality.quality_id = quality.quality_id)
5. 64.872 10,014.535 ↑ 1.5 390,912 1

Hash Left Join (cost=1,658,731.56..1,808,388.90 rows=573,414 width=107) (actual time=8,501.602..10,014.535 rows=390,912 loops=1)

  • Hash Cond: (signals_signal_quality_association.signal_quality_id = signal_quality.signal_quality_id)
6. 85.504 9,944.105 ↑ 1.5 390,912 1

Hash Left Join (cost=1,658,149.30..1,799,922.20 rows=573,414 width=107) (actual time=8,495.922..9,944.105 rows=390,912 loops=1)

  • Hash Cond: (signal.site_id = site.site_id)
7. 1,063.675 9,858.571 ↑ 1.5 390,912 1

Hash Right Join (cost=1,658,146.22..1,792,034.67 rows=573,414 width=95) (actual time=8,495.873..9,858.571 rows=390,912 loops=1)

  • Hash Cond: (signals_signal_quality_association.signal_id = signal.signal_id)
8. 397.047 397.047 ↓ 1.0 4,807,213 1

Seq Scan on signals_signal_quality_association (cost=0.00..69,528.42 rows=4,806,242 width=8) (actual time=0.028..397.047 rows=4,807,213 loops=1)

9. 112.059 8,397.849 ↑ 1.5 390,912 1

Hash (cost=1,642,578.54..1,642,578.54 rows=573,414 width=91) (actual time=8,397.849..8,397.849 rows=390,912 loops=1)

  • Buckets: 32768 Batches: 32 Memory Usage: 1713kB
10. 103.511 8,285.790 ↑ 1.5 390,912 1

Hash Right Join (cost=1,634,679.29..1,642,578.54 rows=573,414 width=91) (actual time=8,182.327..8,285.790 rows=390,912 loops=1)

  • Hash Cond: (signals_comments_association.signal_id = signal.signal_id)
11. 0.001 0.001 ↓ 0.0 0 1

Seq Scan on signals_comments_association (cost=0.00..32.60 rows=2,260 width=8) (actual time=0.001..0.001 rows=0 loops=1)

12. 144.661 8,182.278 ↑ 1.5 390,912 1

Hash (cost=1,619,671.61..1,619,671.61 rows=573,414 width=87) (actual time=8,182.278..8,182.278 rows=390,912 loops=1)

  • Buckets: 32768 Batches: 32 Memory Usage: 1619kB
13. 95.625 8,037.617 ↑ 1.5 390,912 1

Hash Join (cost=443,010.06..1,619,671.61 rows=573,414 width=87) (actual time=2,307.019..8,037.617 rows=390,912 loops=1)

  • Hash Cond: (signal.parameter_id = parameter.parameter_id)
14. 1,903.904 7,941.970 ↑ 2.6 390,912 1

Hash Join (cost=443,008.56..1,610,124.08 rows=1,016,507 width=76) (actual time=2,306.990..7,941.970 rows=390,912 loops=1)

  • Hash Cond: (signal.source_id = source.source_id)
15. 3,747.675 6,038.036 ↑ 1.0 20,459,097 1

Bitmap Heap Scan on signal (cost=443,004.23..1,523,020.38 rows=20,552,943 width=32) (actual time=2,296.782..6,038.036 rows=20,459,097 loops=1)

  • Recheck Cond: (('2018-10-01 00:00:00'::timestamp without time zone <= "timestamp") AND ("timestamp" <= '2019-01-01 00:00:00'::timestamp without time zone))
  • Rows Removed by Index Recheck: 29277
  • Heap Blocks: exact=31134 lossy=184383
16. 2,290.361 2,290.361 ↑ 1.0 20,459,097 1

Bitmap Index Scan on ix_signal_timestamp (cost=0.00..437,866.00 rows=20,552,943 width=0) (actual time=2,290.361..2,290.361 rows=20,459,097 loops=1)

  • Index Cond: (('2018-10-01 00:00:00'::timestamp without time zone <= "timestamp") AND ("timestamp" <= '2019-01-01 00:00:00'::timestamp without time zone))
17. 0.004 0.030 ↑ 2.0 2 1

Hash (cost=4.28..4.28 rows=4 width=52) (actual time=0.030..0.030 rows=2 loops=1)

  • Buckets: 1024 Batches: 1 Memory Usage: 9kB
18. 0.015 0.026 ↑ 2.0 2 1

Hash Join (cost=1.24..4.28 rows=4 width=52) (actual time=0.019..0.026 rows=2 loops=1)

  • Hash Cond: (source.source_type_id = source_type.source_type_id)
19. 0.003 0.003 ↓ 1.1 83 1

Seq Scan on source (cost=0.00..2.73 rows=73 width=38) (actual time=0.001..0.003 rows=83 loops=1)

20. 0.000 0.008 ↑ 1.0 1 1

Hash (cost=1.23..1.23 rows=1 width=22) (actual time=0.008..0.008 rows=1 loops=1)

  • Buckets: 1024 Batches: 1 Memory Usage: 9kB
21. 0.008 0.008 ↑ 1.0 1 1

Seq Scan on source_type (cost=0.00..1.23 rows=1 width=22) (actual time=0.006..0.008 rows=1 loops=1)

  • Filter: ((name)::text = 'Hach_Flo-Dar'::text)
  • Rows Removed by Filter: 18
22. 0.011 0.022 ↓ 2.1 46 1

Hash (cost=1.22..1.22 rows=22 width=19) (actual time=0.022..0.022 rows=46 loops=1)

  • Buckets: 1024 Batches: 1 Memory Usage: 11kB
23. 0.011 0.011 ↓ 2.1 46 1

Seq Scan on parameter (cost=0.00..1.22 rows=22 width=19) (actual time=0.004..0.011 rows=46 loops=1)

24. 0.009 0.030 ↑ 1.0 48 1

Hash (cost=2.48..2.48 rows=48 width=20) (actual time=0.030..0.030 rows=48 loops=1)

  • Buckets: 1024 Batches: 1 Memory Usage: 11kB
25. 0.021 0.021 ↑ 1.0 48 1

Seq Scan on site (cost=0.00..2.48 rows=48 width=20) (actual time=0.009..0.021 rows=48 loops=1)

26. 2.829 5.558 ↑ 1.0 20,145 1

Hash (cost=330.45..330.45 rows=20,145 width=8) (actual time=5.558..5.558 rows=20,145 loops=1)

  • Buckets: 32768 Batches: 1 Memory Usage: 1043kB
27. 2.729 2.729 ↑ 1.0 20,145 1

Seq Scan on signal_quality (cost=0.00..330.45 rows=20,145 width=8) (actual time=0.008..2.729 rows=20,145 loops=1)

28. 0.002 0.010 ↑ 1.0 3 1

Hash (cost=1.03..1.03 rows=3 width=68) (actual time=0.010..0.010 rows=3 loops=1)

  • Buckets: 1024 Batches: 1 Memory Usage: 9kB
29. 0.008 0.008 ↑ 1.0 3 1

Seq Scan on quality (cost=0.00..1.03 rows=3 width=68) (actual time=0.007..0.008 rows=3 loops=1)