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 '%unusual%deposits%'
		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=847721.26..847721.76 rows=200 width=8) (actual time=56498.988..56498.992 rows=45 loops=1)
   Sort Key: (count(*)), (count(orders.o_orderkey))
   Sort Method: quicksort  Memory: 27kB
   Buffers: shared hit=255410 read=33899 written=21
   ->  HashAggregate  (cost=847711.62..847713.62 rows=200 width=8) (actual time=56498.789..56498.798 rows=45 loops=1)
         Group Key: count(orders.o_orderkey)
         Buffers: shared hit=255407 read=33899 written=21
         ->  HashAggregate  (cost=810211.62..825211.62 rows=1500000 width=8) (actual time=55202.070..56161.176 rows=1500000 loops=1)
               Group Key: customer.c_custkey
               Buffers: shared hit=255407 read=33899 written=21
               ->  Hash Right Join  (cost=69028.00..735438.19 rows=14954686 width=8) (actual time=1382.994..30483.911 rows=15338064 loops=1)
                     Hash Cond: (orders.o_custkey = customer.c_custkey)
                     Buffers: shared hit=255407 read=33899 written=21
                     ->  Seq Scan on orders  (cost=0.00..442089.90 rows=14954686 width=8) (actual time=0.028..9539.955 rows=14838045 loops=1)
                           Filter: ((o_comment)::text !~~ '%unusual%deposits%'::text)
                           Rows Removed by Filter: 161955
                           Buffers: shared hit=220129 read=33899 written=21
                     ->  Hash  (cost=50278.00..50278.00 rows=1500000 width=4) (actual time=1365.517..1365.517 rows=1500000 loops=1)
                           Buckets: 2097152  Batches: 1  Memory Usage: 69119kB
                           Buffers: shared hit=35278
                           ->  Seq Scan on customer  (cost=0.00..50278.00 rows=1500000 width=4) (actual time=0.027..740.103 rows=1500000 loops=1)
                                 Buffers: shared hit=35278
 Planning time: 4.078 ms
 Execution time: 56531.983 ms
(24 rows)

COMMIT;
COMMIT