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: 27188.428 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=1536221.11..1536221.61 rows=200 width=16) (actual time=27188.326..27188.410 rows=47 loops=1)
  Sort Key: (count(*)) DESC, (count(orders.o_orderkey)) DESC
  Sort Method: quicksort  Memory: 27kB
  ->  HashAggregate  (cost=1536211.47..1536213.47 rows=200 width=16) (actual time=27188.291..27188.381 rows=47 loops=1)
        Group Key: count(orders.o_orderkey)
        Batches: 1  Memory Usage: 40kB
        ->  Finalize GroupAggregate  (cost=1000.89..1513710.73 rows=1500049 width=12) (actual time=3.943..26841.947 rows=1500000 loops=1)
              Group Key: customer.c_custkey
              ->  Gather Merge  (cost=1000.89..1483709.75 rows=3000098 width=12) (actual time=3.912..26305.328 rows=1500000 loops=1)
                    Workers Planned: 2
                    Workers Launched: 2
                    ->  Partial GroupAggregate  (cost=0.86..1136423.98 rows=1500049 width=12) (actual time=0.115..22216.264 rows=500000 loops=3)
                          Group Key: customer.c_custkey
                          ->  Nested Loop Left Join  (cost=0.86..1090148.46 rows=6255005 width=12) (actual time=0.056..21317.300 rows=5117943 loops=3)
                                ->  Parallel Index Only Scan using pk_customer on customer  (cost=0.43..28594.88 rows=625020 width=4) (actual time=0.024..112.247 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=0.005..0.041 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 |   500019
      10 |    65769
       9 |    65223
      11 |    62498
       8 |    58152
      12 |    55775
      13 |    49917
       7 |    46563
      19 |    46548
      18 |    45998
      20 |    45481
      14 |    45391
      17 |    45138
      16 |    43711
      15 |    43604
      21 |    42614
      22 |    37982
       6 |    32841
      23 |    32680
      24 |    26758
      25 |    21250
       5 |    19520
      26 |    16078
      27 |    11670
       4 |     9954
      28 |     8174
      29 |     5754
       3 |     3951
      30 |     3761
      31 |     2337
      32 |     1513
       2 |     1184
      33 |      882
      34 |      493
      35 |      266
       1 |      234
      36 |      143
      37 |       88
      38 |       37
      39 |       21
      40 |       15
      41 |        5
      42 |        3
      43 |        2
      46 |        1
      45 |        1
      44 |        1
(47 rows)

COMMIT;
COMMIT