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%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=851519.45..851519.95 rows=200 width=8) (actual time=31063.691..31063.693 rows=45 loops=1)
   Sort Key: (count(*)), (count(orders.o_orderkey))
   Sort Method: quicksort  Memory: 27kB
   Buffers: shared hit=190410 read=100925 written=1096
   ->  HashAggregate  (cost=851509.81..851511.81 rows=200 width=8) (actual time=31063.592..31063.600 rows=45 loops=1)
         Group Key: count(orders.o_orderkey)
         Buffers: shared hit=190407 read=100925 written=1096
         ->  HashAggregate  (cost=814009.81..829009.81 rows=1500000 width=8) (actual time=30125.300..30735.460 rows=1500000 loops=1)
               Group Key: customer.c_custkey
               Buffers: shared hit=190407 read=100925 written=1096
               ->  Hash Right Join  (cost=69028.00..739168.30 rows=14968301 width=8) (actual time=990.187..18990.093 rows=15338746 loops=1)
                     Hash Cond: (orders.o_custkey = customer.c_custkey)
                     Buffers: shared hit=190407 read=100925 written=1096
                     ->  Seq Scan on orders  (cost=0.00..445615.79 rows=14968301 width=8) (actual time=0.032..8624.523 rows=14838728 loops=1)
                           Filter: ((o_comment)::text !~~ '%pending%packages%'::text)
                           Rows Removed by Filter: 161272
                           Buffers: shared hit=155130 read=100924 written=1096
                     ->  Hash  (cost=50278.00..50278.00 rows=1500000 width=4) (actual time=982.924..982.924 rows=1500000 loops=1)
                           Buckets: 2097152  Batches: 1  Memory Usage: 69119kB
                           Buffers: shared hit=35277 read=1
                           ->  Seq Scan on customer  (cost=0.00..50278.00 rows=1500000 width=4) (actual time=0.017..575.304 rows=1500000 loops=1)
                                 Buffers: shared hit=35277 read=1
 Planning time: 3.020 ms
 Execution time: 31080.941 ms
(24 rows)

COMMIT;
COMMIT