explain.depesz.com

PostgreSQL's explain analyze made readable

Result: r2v6 : Optimization for: plan #EcGQ

Settings

Optimization path:

Optimization(s) for this plan:

# exclusive inclusive rows x rows loops node
1. 33.378 174.500 ↓ 3.8 1,395 1

HashAggregate (cost=15,420.13..15,423.78 rows=365 width=25) (actual time=174.089..174.500 rows=1,395 loops=1)

  • Group Key: student_id
2. 141.122 141.122 ↑ 1.1 84,779 1

Seq Scan on questions (cost=0.00..14,973.09 rows=89,408 width=25) (actual time=0.122..141.122 rows=84,779 loops=1)

  • Filter: (has_revised IS TRUE)
  • Rows Removed by Filter: 339,840
Planning time : 0.197 ms
Execution time : 174.658 ms