load 'auto_explain';
LOAD
set auto_explain.log_min_duration to 0;
SET
set auto_explain.log_analyze to on;
SET
set auto_explain.log_wal to on;
SET
set auto_explain.log_timing to on;
SET
set auto_explain.log_level to notice;
SET
BEGIN;
BEGIN
select
	c_count,
	count(*) as custdist
from
	(
		select
			c_custkey,
			count(o_orderkey)
		from
			customer left outer join orders on
				c_custkey = o_custkey
				and o_comment not like '%express%accounts%'
		group by
			c_custkey
	) as c_orders (c_custkey, c_count)
group by
	c_count
order by
	custdist desc,
	c_count desc;
NOTICE:  duration: 68104.400 ms  plan:
Query Text: select
	c_count,
	count(*) as custdist
from
	(
		select
			c_custkey,
			count(o_orderkey)
		from
			customer left outer join orders on
				c_custkey = o_custkey
				and o_comment not like '%express%accounts%'
		group by
			c_custkey
	) as c_orders (c_custkey, c_count)
group by
	c_count
order by
	custdist desc,
	c_count desc;
Sort  (cost=1537708.04..1537708.54 rows=200 width=16) (actual time=68095.069..68104.365 rows=46 loops=1)
  Sort Key: (count(*)) DESC, (count(orders.o_orderkey)) DESC
  Sort Method: quicksort  Memory: 27kB
  ->  HashAggregate  (cost=1537698.39..1537700.39 rows=200 width=16) (actual time=68094.982..68104.288 rows=46 loops=1)
        Group Key: count(orders.o_orderkey)
        Batches: 1  Memory Usage: 40kB
        ->  Finalize GroupAggregate  (cost=1000.89..1515197.66 rows=1500049 width=12) (actual time=27.543..67162.900 rows=1500000 loops=1)
              Group Key: customer.c_custkey
              ->  Gather Merge  (cost=1000.89..1485196.68 rows=3000098 width=12) (actual time=27.473..65779.139 rows=1500000 loops=1)
                    Workers Planned: 2
                    Workers Launched: 2
                    ->  Partial GroupAggregate  (cost=0.86..1137910.91 rows=1500049 width=12) (actual time=0.278..56396.868 rows=500000 loops=3)
                          Group Key: customer.c_custkey
                          ->  Nested Loop Left Join  (cost=0.86..1091541.80 rows=6273724 width=12) (actual time=0.144..54056.519 rows=5112987 loops=3)
                                ->  Parallel Index Only Scan using pk_customer on customer  (cost=0.43..28594.88 rows=625020 width=4) (actual time=0.073..303.827 rows=500000 loops=3)
                                      Heap Fetches: 0
                                ->  Index Scan using orders_o_custkey_idx on orders  (cost=0.43..1.53 rows=17 width=12) (actual time=0.013..0.103 rows=10 loops=1500000)
                                      Index Cond: (o_custkey = customer.c_custkey)
                                      Filter: ((o_comment)::text !~~ '%express%accounts%'::text)
                                      Rows Removed by Filter: 0
 c_count | custdist 
---------+----------
       0 |   500017
      10 |    65927
       9 |    65303
      11 |    62521
       8 |    58343
      12 |    55656
      13 |    49883
      19 |    46725
       7 |    46518
      18 |    46039
      14 |    45528
      20 |    45390
      17 |    45181
      16 |    43733
      15 |    43606
      21 |    42424
      22 |    37880
       6 |    33022
      23 |    32541
      24 |    26696
      25 |    21191
       5 |    19646
      26 |    15932
      27 |    11608
       4 |     9990
      28 |     8135
      29 |     5615
       3 |     3986
      30 |     3766
      31 |     2368
      32 |     1476
       2 |     1188
      33 |      865
      34 |      490
      35 |      262
       1 |      237
      36 |      145
      37 |       84
      38 |       30
      39 |       25
      40 |       15
      41 |        5
      42 |        3
      45 |        2
      43 |        2
      44 |        1
(46 rows)

COMMIT;
COMMIT