explain.depesz.com

PostgreSQL's explain analyze made readable

Result: WBlE

Settings
# exclusive inclusive rows x rows loops node
1. 0.037 42,088.558 ↑ 1.0 97 1

Sort (cost=5,607,773.23..5,607,773.48 rows=97 width=12) (actual time=42,088.551..42,088.558 rows=97 loops=1)

  • Sort Key: (max(signal."timestamp"))
  • Sort Method: quicksort Memory: 29kB
2. 0.308 42,088.521 ↑ 1.0 97 1

HashAggregate (cost=5,607,769.06..5,607,770.03 rows=97 width=12) (actual time=42,088.505..42,088.521 rows=97 loops=1)

  • Group Key: latest.source_id
3. 28,415.114 42,088.213 ↑ 82,506.4 584 1

Hash Join (cost=3.18..5,366,850.50 rows=48,183,712 width=12) (actual time=389.818..42,088.213 rows=584 loops=1)

  • Hash Cond: (signal.source_id = latest.source_id)
  • Join Filter: (signal."timestamp" >= latest.max)
  • Rows Removed by Join Filter: 144550557
4. 13,673.057 13,673.057 ↓ 1.0 144,551,141 1

Seq Scan on signal (cost=0.00..3,017,891.36 rows=144,551,136 width=12) (actual time=0.030..13,673.057 rows=144,551,141 loops=1)

5. 0.025 0.042 ↑ 1.0 97 1

Hash (cost=1.97..1.97 rows=97 width=12) (actual time=0.042..0.042 rows=97 loops=1)

  • Buckets: 1024 Batches: 1 Memory Usage: 13kB
6. 0.017 0.017 ↑ 1.0 97 1

Seq Scan on latest (cost=0.00..1.97 rows=97 width=12) (actual time=0.005..0.017 rows=97 loops=1)