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%packages%'
		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=920930.09..920930.59 rows=200 width=8) (actual time=88780.110..88780.114 rows=46 loops=1)
   Sort Key: (count(*)), (count(orders.o_orderkey))
   Sort Method: quicksort  Memory: 27kB
   Buffers: shared hit=225916 read=63140
   ->  HashAggregate  (cost=920920.45..920922.45 rows=200 width=8) (actual time=88779.993..88780.004 rows=46 loops=1)
         Buffers: shared hit=225913 read=63140
         ->  HashAggregate  (cost=883420.45..898420.45 rows=1500000 width=8) (actual time=87549.686..88422.571 rows=1500000 loops=1)
               Buffers: shared hit=225913 read=63140
               ->  Hash Right Join  (cost=69028.00..808871.88 rows=14909714 width=8) (actual time=3815.912..65134.419 rows=15352734 loops=1)
                     Hash Cond: (orders.o_custkey = customer.c_custkey)
                     Buffers: shared hit=225913 read=63140
                     ->  Seq Scan on orders  (cost=0.00..441649.60 rows=14909714 width=8) (actual time=0.052..19023.277 rows=14852713 loops=1)
                           Filter: ((o_comment)::text !~~ '%unusual%packages%'::text)
                           Rows Removed by Filter: 162287
                           Buffers: shared hit=223392 read=30383
                     ->  Hash  (cost=50278.00..50278.00 rows=1500000 width=4) (actual time=3813.499..3813.499 rows=1500000 loops=1)
                           Buckets: 262144  Batches: 1  Memory Usage: 52735kB
                           Buffers: shared hit=2521 read=32757
                           ->  Seq Scan on customer  (cost=0.00..50278.00 rows=1500000 width=4) (actual time=0.021..3052.755 rows=1500000 loops=1)
                                 Buffers: shared hit=2521 read=32757
 Total runtime: 88826.640 ms
(21 rows)

COMMIT;
COMMIT