explain.depesz.com

PostgreSQL's explain analyze made readable

Result: SM6O : normal join-partial on mapping_target

Settings
# exclusive inclusive rows x rows loops node
1. 0.014 125.912 ↓ 1.3 4 1

Merge Join (cost=14,171.87..14,172.12 rows=3 width=110) (actual time=125.898..125.912 rows=4 loops=1)

  • Merge Cond: (c.event_id = cet.id)
2. 0.008 125.868 ↓ 1.3 4 1

Merge Left Join (cost=14,170.81..14,171.01 rows=3 width=95) (actual time=125.859..125.868 rows=4 loops=1)

  • Merge Cond: (c.event_id = c1.event_id)
3. 0.010 0.023 ↓ 1.3 4 1

Sort (cost=12.20..12.21 rows=3 width=87) (actual time=0.022..0.023 rows=4 loops=1)

  • Sort Key: c.event_id
  • Sort Method: quicksort Memory: 25kB
4. 0.013 0.013 ↓ 1.3 4 1

Index Scan using coupon_mapping_primary_index on coupon c (cost=0.13..12.18 rows=3 width=87) (actual time=0.008..0.013 rows=4 loops=1)

5. 0.005 125.837 ↓ 1.2 5 1

Materialize (cost=14,158.62..14,158.77 rows=4 width=24) (actual time=125.832..125.837 rows=5 loops=1)

6. 0.008 125.832 ↓ 1.2 5 1

Finalize GroupAggregate (cost=14,158.62..14,158.72 rows=4 width=40) (actual time=125.828..125.832 rows=5 loops=1)

  • Group Key: c1.event_id
7. 0.000 125.824 ↓ 1.4 11 1

Sort (cost=14,158.62..14,158.64 rows=8 width=24) (actual time=125.823..125.824 rows=11 loops=1)

  • Sort Key: c1.event_id
  • Sort Method: quicksort Memory: 25kB
8. 14.140 126.154 ↓ 1.4 11 1

Gather (cost=14,157.66..14,158.50 rows=8 width=24) (actual time=118.574..126.154 rows=11 loops=1)

  • Workers Planned: 2
  • Workers Launched: 2
9. 11.571 112.014 ↑ 1.0 4 3 / 3

Partial HashAggregate (cost=13,157.66..13,157.70 rows=4 width=24) (actual time=112.014..112.014 rows=4 loops=3)

  • Group Key: c1.event_id
10. 14.939 100.443 ↑ 1.3 27,299 3 / 3

Hash Left Join (cost=1,578.83..12,816.22 rows=34,144 width=28) (actual time=57.275..100.443 rows=27,299 loops=3)

  • Hash Cond: (c1.id = ce.coupon_id)
11. 28.481 28.481 ↑ 1.3 27,299 3 / 3

Parallel Seq Scan on coupon c1 (cost=0.00..11,147.76 rows=34,144 width=40) (actual time=0.003..28.481 rows=27,299 loops=3)

  • Filter: (type = 0)
  • Rows Removed by Filter: 3278
12. 32.721 57.023 ↑ 1.0 54,659 3 / 3

Hash (cost=895.59..895.59 rows=54,659 width=20) (actual time=57.023..57.023 rows=54,659 loops=3)

  • Buckets: 65536 Batches: 1 Memory Usage: 3288kB
13. 24.302 24.302 ↑ 1.0 54,659 3 / 3

Seq Scan on coupon_ext ce (cost=0.00..895.59 rows=54,659 width=20) (actual time=0.013..24.302 rows=54,659 loops=3)

14. 0.020 0.030 ↓ 1.3 4 1

Sort (cost=1.05..1.06 rows=3 width=29) (actual time=0.030..0.030 rows=4 loops=1)

  • Sort Key: cet.id
  • Sort Method: quicksort Memory: 25kB
15. 0.010 0.010 ↓ 1.3 4 1

Seq Scan on coupon_event cet (cost=0.00..1.03 rows=3 width=29) (actual time=0.008..0.010 rows=4 loops=1)

Planning time : 0.929 ms
Execution time : 126.723 ms