explain.depesz.com

PostgreSQL's explain analyze made readable

Result: mCfdb

Settings
# exclusive inclusive rows x rows loops node
1. 0.000 0.000 ↓ 0.0

HashAggregate (cost=94.35..97.90 rows=203 width=68) (actual rows= loops=)

  • Group Key: s.student_id
2. 0.000 0.000 ↓ 0.0

Hash Right Join (cost=57.93..93.33 rows=203 width=72) (actual rows= loops=)

  • Hash Cond: (em2.student_id = s.student_id)
3. 0.000 0.000 ↓ 0.0

Seq Scan on exam_marks em2 (cost=0.00..27.00 rows=1,700 width=8) (actual rows= loops=)

4. 0.000 0.000 ↓ 0.0

Hash (cost=57.09..57.09 rows=67 width=68) (actual rows= loops=)

5. 0.000 0.000 ↓ 0.0

Hash Join (cost=40.01..57.09 rows=67 width=68) (actual rows= loops=)

  • Hash Cond: (s.student_id = em.student_id)
6. 0.000 0.000 ↓ 0.0

Seq Scan on student s (cost=0.00..15.60 rows=560 width=68) (actual rows= loops=)

7. 0.000 0.000 ↓ 0.0

Hash (cost=39.17..39.17 rows=67 width=4) (actual rows= loops=)

8. 0.000 0.000 ↓ 0.0

HashAggregate (cost=35.50..38.50 rows=67 width=4) (actual rows= loops=)

  • Group Key: em.student_id
  • Filter: (avg(em.mark) > 4.1)
9. 0.000 0.000 ↓ 0.0

Seq Scan on exam_marks em (cost=0.00..27.00 rows=1,700 width=8) (actual rows= loops=)