explain.depesz.com

PostgreSQL's explain analyze made readable

Result: TfYh : Optimization for: plan #sg35

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Optimization path:

Optimization(s) for this plan:

# exclusive inclusive rows x rows loops node
1. 0.002 0.036 ↑ 1.0 1 1

Limit (cost=0.69..10.78 rows=1 width=189) (actual time=0.034..0.036 rows=1 loops=1)

2. 0.002 0.034 ↑ 21.0 1 1

Nested Loop Left Join (cost=0.69..212.47 rows=21 width=189) (actual time=0.034..0.034 rows=1 loops=1)

  • Join Filter: (nodeslogical.nl_id = wifiaccesspointsassignmenthistory.wapah_nl_id)
  • Rows Removed by Join Filter: 4
3. 0.001 0.023 ↑ 21.0 1 1

Nested Loop Left Join (cost=0.69..136.97 rows=21 width=35) (actual time=0.023..0.023 rows=1 loops=1)

4. 0.003 0.020 ↑ 21.0 1 1

Nested Loop (cost=0.55..85.05 rows=21 width=37) (actual time=0.020..0.020 rows=1 loops=1)

5. 0.012 0.012 ↑ 21.0 1 1

Index Only Scan using watph_wat_mac_index on wifiaeroscouttagspositionhistory (cost=0.28..42.95 rows=21 width=22) (actual time=0.012..0.012 rows=1 loops=1)

  • Index Cond: (watph_wat_mac = '00:0c:cc:49:17:64'::macaddr)
  • Heap Fetches: 1
6. 0.005 0.005 ↑ 1.0 1 1

Index Scan using wifiaccesspoints_pkey on wifiaccesspoints (cost=0.27..2.00 rows=1 width=15) (actual time=0.005..0.005 rows=1 loops=1)

  • Index Cond: (wap_basemac = wifiaeroscouttagspositionhistory.watph_wap_basemac)
7. 0.002 0.002 ↓ 0.0 0 1

Index Scan using wapah_unique_active_mac on wifiaccesspointsassignmenthistory (cost=0.14..2.45 rows=1 width=10) (actual time=0.002..0.002 rows=0 loops=1)

  • Index Cond: (wapah_basemac = wifiaeroscouttagspositionhistory.watph_wap_basemac)
8. 0.003 0.009 ↑ 50.0 4 1

Materialize (cost=0.00..13.00 rows=200 width=158) (actual time=0.007..0.009 rows=4 loops=1)

9. 0.006 0.006 ↑ 50.0 4 1

Seq Scan on nodeslogical (cost=0.00..12.00 rows=200 width=158) (actual time=0.005..0.006 rows=4 loops=1)