BEGIN;
BEGIN
EXPLAIN (ANALYZE, BUFFERS)
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 '%pending%accounts%'
		group by
			c_custkey
	) as c_orders (c_custkey, c_count)
group by
	c_count
order by
	custdist desc,
	c_count desc;
                                                                    QUERY PLAN                                                                     
---------------------------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=927986.48..927986.98 rows=200 width=8) (actual time=67231.015..67231.015 rows=46 loops=1)
   Sort Key: (count(*)), (count(orders.o_orderkey))
   Sort Method: quicksort  Memory: 27kB
   Buffers: shared hit=233719 read=58122 written=449
   ->  HashAggregate  (cost=927976.84..927978.84 rows=200 width=8) (actual time=67230.912..67230.927 rows=46 loops=1)
         Buffers: shared hit=233716 read=58122 written=449
         ->  HashAggregate  (cost=890476.84..905476.84 rows=1500000 width=8) (actual time=65999.128..66872.040 rows=1500000 loops=1)
               Buffers: shared hit=233716 read=58122 written=449
               ->  Hash Right Join  (cost=69028.00..815486.35 rows=14998098 width=8) (actual time=1922.389..47431.754 rows=15353138 loops=1)
                     Hash Cond: (orders.o_custkey = customer.c_custkey)
                     Buffers: shared hit=233716 read=58122 written=449
                     ->  Seq Scan on orders  (cost=0.00..446496.39 rows=14998098 width=8) (actual time=0.040..10713.588 rows=14853122 loops=1)
                           Filter: ((o_comment)::text !~~ '%pending%accounts%'::text)
                           Rows Removed by Filter: 161878
                           Buffers: shared hit=233714 read=22846 written=449
                     ->  Hash  (cost=50278.00..50278.00 rows=1500000 width=4) (actual time=1920.625..1920.625 rows=1500000 loops=1)
                           Buckets: 262144  Batches: 1  Memory Usage: 52735kB
                           Buffers: shared hit=2 read=35276
                           ->  Seq Scan on customer  (cost=0.00..50278.00 rows=1500000 width=4) (actual time=0.041..1166.306 rows=1500000 loops=1)
                                 Buffers: shared hit=2 read=35276
 Total runtime: 67761.531 ms
(21 rows)

COMMIT;
COMMIT