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=924248.67..924249.17 rows=200 width=8) (actual time=75378.079..75378.081 rows=45 loops=1)
   Sort Key: (count(*)), (count(orders.o_orderkey))
   Sort Method: quicksort  Memory: 27kB
   Buffers: shared hit=225584 read=64738 written=4418
   ->  HashAggregate  (cost=924239.03..924241.03 rows=200 width=8) (actual time=75377.952..75377.963 rows=45 loops=1)
         Buffers: shared hit=225581 read=64738 written=4418
         ->  HashAggregate  (cost=886739.03..901739.03 rows=1500000 width=8) (actual time=74143.228..75021.705 rows=1500000 loops=1)
               Buffers: shared hit=225581 read=64738 written=4418
               ->  Hash Right Join  (cost=69028.00..811967.39 rows=14954327 width=8) (actual time=3574.706..55031.428 rows=15338054 loops=1)
                     Hash Cond: (orders.o_custkey = customer.c_custkey)
                     Buffers: shared hit=225581 read=64738 written=4418
                     ->  Seq Scan on orders  (cost=0.00..443852.85 rows=14954327 width=8) (actual time=0.036..12912.710 rows=14838035 loops=1)
                           Filter: ((o_comment)::text !~~ '%unusual%deposits%'::text)
                           Rows Removed by Filter: 161965
                           Buffers: shared hit=219710 read=35331 written=961
                     ->  Hash  (cost=50278.00..50278.00 rows=1500000 width=4) (actual time=3573.092..3573.092 rows=1500000 loops=1)
                           Buckets: 262144  Batches: 1  Memory Usage: 52735kB
                           Buffers: shared hit=5871 read=29407 written=3457
                           ->  Seq Scan on customer  (cost=0.00..50278.00 rows=1500000 width=4) (actual time=0.016..1690.310 rows=1500000 loops=1)
                                 Buffers: shared hit=5871 read=29407 written=3457
 Total runtime: 75435.271 ms
(21 rows)

COMMIT;
COMMIT