explain.depesz.com

PostgreSQL's explain analyze made readable

Result: VeLD

Settings
# exclusive inclusive rows x rows loops node
1. 3.707 128,618.515 ↑ 1.1 1,876 1

Seq Scan on symbols s (cost=0.00..189,346.32 rows=2,028 width=20) (actual time=0.349..128,618.515 rows=1,876 loops=1)

2.          

SubPlan (forSeq Scan)

3. 3.752 128,337.160 ↑ 1.0 1 1,876

Limit (cost=2.55..46.68 rows=1 width=16) (actual time=68.409..68.410 rows=1 loops=1,876)

4. 0.000 128,333.408 ↑ 12,919.0 1 1,876

Custom Scan (ConstraintAwareAppend) (cost=2.55..570,112.19 rows=12,919 width=16) (actual time=68.408..68.408 rows=1 loops=1,876)

  • Hypertable: tickers
  • Chunks left after exclusion: 1
5. 1.876 128,333.408 ↑ 12,919.0 1 1,876

Merge Append (cost=2.55..570,112.19 rows=12,919 width=16) (actual time=68.408..68.408 rows=1 loops=1,876)

  • Sort Key: t_1."time
6. 128,331.532 128,331.532 ↑ 12,913.0 1 1,876

Index Scan using _hyper_1_5_chunk_time_symbol_idx on _hyper_1_5_chunk t_1 (cost=0.58..569,884.67 rows=12,913 width=16) (actual time=68.407..68.407 rows=1 loops=1,876)

  • Index Cond: (("time" > (now() - '1 mon'::interval)) AND ((symbol)::text = (s.symbol)::text))
7. 5.628 277.648 ↑ 1.0 1 1,876

Limit (cost=2.55..46.68 rows=1 width=16) (actual time=0.147..0.148 rows=1 loops=1,876)

8. 0.000 272.020 ↑ 12,919.0 1 1,876

Custom Scan (ConstraintAwareAppend) (cost=2.55..570,112.19 rows=12,919 width=16) (actual time=0.145..0.145 rows=1 loops=1,876)

  • Hypertable: tickers
  • Chunks left after exclusion: 1
9. 0.000 272.020 ↑ 12,919.0 1 1,876

Merge Append (cost=2.55..570,112.19 rows=12,919 width=16) (actual time=0.145..0.145 rows=1 loops=1,876)

  • Sort Key: t_3."time" DESC
10. 272.020 272.020 ↑ 12,913.0 1 1,876

Index Scan Backward using _hyper_1_5_chunk_time_symbol_idx on _hyper_1_5_chunk t_3 (cost=0.58..569,884.67 rows=12,913 width=16) (actual time=0.145..0.145 rows=1 loops=1,876)

  • Index Cond: (("time" > (now() - '1 mon'::interval)) AND ((symbol)::text = (s.symbol)::text))