explain.depesz.com

PostgreSQL's explain analyze made readable

Result: QlMj : normal join

Settings
# exclusive inclusive rows x rows loops node
1. 0.020 128.821 ↓ 1.3 4 1

Hash Join (cost=14,159.87..25,976.63 rows=3 width=110) (actual time=101.071..128.821 rows=4 loops=1)

  • Hash Cond: (c.event_id = cet.id)
2. 0.011 128.786 ↓ 1.3 4 1

Hash Left Join (cost=14,158.81..25,975.46 rows=3 width=95) (actual time=101.043..128.786 rows=4 loops=1)

  • Hash Cond: (c.event_id = "grouping".event_id)
3. 27.750 27.750 ↓ 1.3 4 1

Seq Scan on coupon c (cost=0.00..11,816.62 rows=3 width=87) (actual time=0.011..27.750 rows=4 loops=1)

  • Filter: (mapping_target = 0)
  • Rows Removed by Filter: 91726
4. 0.005 101.025 ↑ 1.0 4 1

Hash (cost=14,158.76..14,158.76 rows=4 width=24) (actual time=101.025..101.025 rows=4 loops=1)

  • Buckets: 1024 Batches: 1 Memory Usage: 9kB
5. 0.002 101.020 ↓ 1.2 5 1

Subquery Scan on grouping (cost=14,158.62..14,158.76 rows=4 width=24) (actual time=101.016..101.020 rows=5 loops=1)

6. 0.006 101.018 ↓ 1.2 5 1

Finalize GroupAggregate (cost=14,158.62..14,158.72 rows=4 width=40) (actual time=101.015..101.018 rows=5 loops=1)

  • Group Key: c1.event_id
7. 0.000 101.012 ↓ 1.5 12 1

Sort (cost=14,158.62..14,158.64 rows=8 width=24) (actual time=101.011..101.012 rows=12 loops=1)

  • Sort Key: c1.event_id
  • Sort Method: quicksort Memory: 25kB
8. 13.070 101.055 ↓ 1.5 12 1

Gather (cost=14,157.66..14,158.50 rows=8 width=24) (actual time=100.987..101.055 rows=12 loops=1)

  • Workers Planned: 2
  • Workers Launched: 2
9. 15.156 87.985 ↑ 1.0 4 3 / 3

Partial HashAggregate (cost=13,157.66..13,157.70 rows=4 width=24) (actual time=87.984..87.985 rows=4 loops=3)

  • Group Key: c1.event_id
10. 14.511 72.829 ↑ 1.3 27,299 3 / 3

Hash Left Join (cost=1,578.83..12,816.22 rows=34,144 width=28) (actual time=30.731..72.829 rows=27,299 loops=3)

  • Hash Cond: (c1.id = ce.coupon_id)
11. 27.846 27.846 ↑ 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=0.004..27.846 rows=27,299 loops=3)

  • Filter: (type = 0)
  • Rows Removed by Filter: 3278
12. 18.820 30.472 ↑ 1.0 54,659 3 / 3

Hash (cost=895.59..895.59 rows=54,659 width=20) (actual time=30.472..30.472 rows=54,659 loops=3)

  • Buckets: 65536 Batches: 1 Memory Usage: 3288kB
13. 11.652 11.652 ↑ 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..11.652 rows=54,659 loops=3)

14. 0.007 0.015 ↓ 1.3 4 1

Hash (cost=1.03..1.03 rows=3 width=29) (actual time=0.015..0.015 rows=4 loops=1)

  • Buckets: 1024 Batches: 1 Memory Usage: 9kB
15. 0.008 0.008 ↓ 1.3 4 1

Seq Scan on coupon_event cet (cost=0.00..1.03 rows=3 width=29) (actual time=0.007..0.008 rows=4 loops=1)

Planning time : 0.593 ms
Execution time : 129.397 ms