explain.depesz.com

PostgreSQL's explain analyze made readable

Result: LBSK

Settings
# exclusive inclusive rows x rows loops node
1. 3.039 47,500.839 ↓ 1.0 1,841 1

Seq Scan on symbols s (cost=0.00..2,797,467.06 rows=1,838 width=20) (actual time=1.647..47,500.839 rows=1,841 loops=1)

2.          

SubPlan (forSeq Scan)

3. 3.682 37,688.952 ↑ 1.0 1 1,841

Limit (cost=726.68..761.00 rows=1 width=16) (actual time=20.471..20.472 rows=1 loops=1,841)

4. 0.000 37,685.270 ↑ 3,548.0 1 1,841

Custom Scan (ConstraintAwareAppend) (cost=726.68..122,499.62 rows=3,548 width=16) (actual time=20.470..20.470 rows=1 loops=1,841)

  • Hypertable: tickers
  • Chunks left after exclusion: 2
5. 0.000 37,685.270 ↑ 3,548.0 1 1,841

Merge Append (cost=726.68..122,499.62 rows=3,548 width=16) (actual time=20.470..20.470 rows=1 loops=1,841)

  • Sort Key: t_1."time
6. 12,041.981 12,041.981 ↑ 317.0 1 1,841

Index Scan Backward using _hyper_1_2049_chunk_tickers_time_idx on _hyper_1_2049_chunk t_1 (cost=0.43..24,874.53 rows=317 width=16) (actual time=6.541..6.541 rows=1 loops=1,841)

  • Index Cond: ("time" > (now() - '1 day'::interval))
  • Filter: ((symbol)::text = (s.symbol)::text)
  • Rows Removed by Filter: 16731
7. 25,643.289 25,643.289 ↑ 1,182.0 1 1,841

Index Scan Backward using _hyper_1_2050_chunk_tickers_time_idx on _hyper_1_2050_chunk t_2 (cost=0.43..92,270.90 rows=1,182 width=16) (actual time=13.929..13.929 rows=1 loops=1,841)

  • Index Cond: ("time" > (now() - '1 day'::interval))
  • Filter: ((symbol)::text = (s.symbol)::text)
  • Rows Removed by Filter: 34579
8. 1.841 9,808.848 ↑ 1.0 1 1,841

Limit (cost=726.68..761.00 rows=1 width=16) (actual time=5.328..5.328 rows=1 loops=1,841)

9. 1.841 9,807.007 ↑ 3,548.0 1 1,841

Custom Scan (ConstraintAwareAppend) (cost=726.68..122,499.62 rows=3,548 width=16) (actual time=5.327..5.327 rows=1 loops=1,841)

  • Hypertable: tickers
  • Chunks left after exclusion: 2
10. 0.000 9,805.166 ↑ 3,548.0 1 1,841

Merge Append (cost=726.68..122,499.62 rows=3,548 width=16) (actual time=5.326..5.326 rows=1 loops=1,841)

  • Sort Key: t_4."time" DESC
11. 9,481.150 9,481.150 ↑ 317.0 1 1,841

Index Scan using _hyper_1_2049_chunk_tickers_time_idx on _hyper_1_2049_chunk t_4 (cost=0.43..24,874.53 rows=317 width=16) (actual time=5.150..5.150 rows=1 loops=1,841)

  • Index Cond: ("time" > (now() - '1 day'::interval))
  • Filter: ((symbol)::text = (s.symbol)::text)
  • Rows Removed by Filter: 14109
12. 324.016 324.016 ↑ 1,182.0 1 1,841

Index Scan using _hyper_1_2050_chunk_tickers_time_idx on _hyper_1_2050_chunk t_5 (cost=0.43..92,270.90 rows=1,182 width=16) (actual time=0.176..0.176 rows=1 loops=1,841)

  • Index Cond: ("time" > (now() - '1 day'::interval))
  • Filter: ((symbol)::text = (s.symbol)::text)
  • Rows Removed by Filter: 935