######## rep_semester_growth ########
Sort  (cost=14562.60..14562.77 rows=67 width=156) (actual time=130.220..130.225 rows=20.00 loops=1)
  Sort Key: cur.chrono
  Sort Method: quicksort  Memory: 26kB
  Buffers: shared hit=1026, temp read=361 written=362
  CTE semester_stats
    ->  GroupAggregate  (cost=13146.60..14346.95 rows=20 width=40) (actual time=112.102..129.943 rows=20.00 loops=1)
          Group Key: a.id, (((a.year * 10) + CASE a.type WHEN 'summer'::semester_type THEN 1 ELSE 2 END))
          Buffers: shared hit=1022, temp read=361 written=362
          ->  Sort  (cost=13146.60..13346.60 rows=80000 width=28) (actual time=111.166..118.496 rows=80000.00 loops=1)
                Sort Key: a.id, (((a.year * 10) + CASE a.type WHEN 'summer'::semester_type THEN 1 ELSE 2 END)), es.id
                Sort Method: external merge  Disk: 2888kB
                Buffers: shared hit=1022, temp read=361 written=362
                ->  Hash Left Join  (cost=2132.45..4717.02 rows=80000 width=28) (actual time=16.506..66.606 rows=80000.00 loops=1)
                      Hash Cond: (ss.id = ps.enrolled_id)
                      Buffers: shared hit=1022
                      ->  Hash Right Join  (cost=515.45..2290.01 rows=80000 width=20) (actual time=3.651..37.227 rows=80000.00 loops=1)
                            Hash Cond: (es.semester_id = a.id)
                            Buffers: shared hit=665
                            ->  Hash Right Join  (cost=514.00..2034.06 rows=80000 width=12) (actual time=3.628..24.767 rows=80000.00 loops=1)
                                  Hash Cond: (ss.enrolled_semesters_id = es.id)
                                  Buffers: shared hit=664
                                  ->  Seq Scan on semesters_subjects ss  (cost=0.00..1310.00 rows=80000 width=8) (actual time=0.010..4.829 rows=80000.00 loops=1)
                                        Buffers: shared hit=510
                                  ->  Hash  (cost=314.00..314.00 rows=16000 width=8) (actual time=3.567..3.567 rows=16000.00 loops=1)
                                        Buckets: 16384  Batches: 1  Memory Usage: 753kB
                                        Buffers: shared hit=154
                                        ->  Seq Scan on enrolled_semesters es  (cost=0.00..314.00 rows=16000 width=8) (actual time=0.010..2.060 rows=16000.00 loops=1)
                                              Buffers: shared hit=154
                            ->  Hash  (cost=1.20..1.20 rows=20 width=12) (actual time=0.016..0.016 rows=20.00 loops=1)
                                  Buckets: 1024  Batches: 1  Memory Usage: 9kB
                                  Buffers: shared hit=1
                                  ->  Seq Scan on active_semesters a  (cost=0.00..1.20 rows=20 width=12) (actual time=0.011..0.012 rows=20.00 loops=1)
                                        Buffers: shared hit=1
                      ->  Hash  (cost=917.00..917.00 rows=56000 width=8) (actual time=12.745..12.745 rows=56000.00 loops=1)
                            Buckets: 65536  Batches: 1  Memory Usage: 2700kB
                            Buffers: shared hit=357
                            ->  Seq Scan on passed_subjects ps  (cost=0.00..917.00 rows=56000 width=8) (actual time=0.010..5.858 rows=56000.00 loops=1)
                                  Buffers: shared hit=357
  ->  Nested Loop Left Join  (cost=0.00..213.62 rows=67 width=156) (actual time=130.017..130.212 rows=20.00 loops=1)
        Join Filter: ((prev.chrono < cur.chrono) AND (NOT EXISTS(SubPlan 2)))
        Rows Removed by Join Filter: 381
        Buffers: shared hit=1026, temp read=361 written=362
        ->  CTE Scan on semester_stats cur  (cost=0.00..0.40 rows=20 width=36) (actual time=112.105..112.106 rows=20.00 loops=1)
              Storage: Memory  Maximum Storage: 18kB
              Buffers: shared hit=1022, temp read=336 written=362
        ->  CTE Scan on semester_stats prev  (cost=0.00..0.40 rows=20 width=20) (actual time=0.000..0.045 rows=20.00 loops=20)
              Storage: Memory  Maximum Storage: 18kB
        SubPlan 2
          ->  CTE Scan on semester_stats mid  (cost=0.00..0.50 rows=1 width=0) (actual time=0.090..0.090 rows=0.90 loops=190)
                Filter: ((chrono < cur.chrono) AND (chrono > prev.chrono))
                Rows Removed by Filter: 8
                Storage: Memory  Maximum Storage: 18kB
                Buffers: temp read=25
Planning:
  Buffers: shared hit=314
Planning Time: 11.066 ms
Execution Time: 138.077 ms
-- OK explain_rep_semester_growth.sql