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=930309.68..930310.18 rows=200 width=8) (actual time=86483.461..86483.464 rows=45 loops=1)
   Sort Key: (count(*)), (count(orders.o_orderkey))
   Sort Method: quicksort  Memory: 27kB
   Buffers: shared hit=274064 read=18030 written=302
   ->  HashAggregate  (cost=930300.04..930302.04 rows=200 width=8) (actual time=86483.336..86483.348 rows=45 loops=1)
         Buffers: shared hit=274061 read=18030 written=302
         ->  HashAggregate  (cost=892800.04..907800.04 rows=1500000 width=8) (actual time=85299.405..86120.468 rows=1500000 loops=1)
               Buffers: shared hit=274061 read=18030 written=302
               ->  Hash Right Join  (cost=69028.00..817432.97 rows=15073414 width=8) (actual time=2300.307..61587.927 rows=15353157 loops=1)
                     Hash Cond: (orders.o_custkey = customer.c_custkey)
                     Buffers: shared hit=274061 read=18030 written=302
                     ->  Seq Scan on orders  (cost=0.00..446936.69 rows=15073414 width=8) (actual time=0.031..18477.328 rows=14853141 loops=1)
                           Filter: ((o_comment)::text !~~ '%pending%accounts%'::text)
                           Rows Removed by Filter: 161859
                           Buffers: shared hit=241176 read=15637 written=302
                     ->  Hash  (cost=50278.00..50278.00 rows=1500000 width=4) (actual time=2298.207..2298.207 rows=1500000 loops=1)
                           Buckets: 262144  Batches: 1  Memory Usage: 52735kB
                           Buffers: shared hit=32885 read=2393
                           ->  Seq Scan on customer  (cost=0.00..50278.00 rows=1500000 width=4) (actual time=0.019..1530.686 rows=1500000 loops=1)
                                 Buffers: shared hit=32885 read=2393
 Total runtime: 86529.237 ms
(21 rows)

COMMIT;
COMMIT