BEGIN;
BEGIN
EXPLAIN (ANALYZE, BUFFERS)
select
	c_custkey,
	c_name,
	sum(l_extendedprice * (1 - l_discount)) as revenue,
	c_acctbal,
	n_name,
	c_address,
	c_phone,
	c_comment
from
	customer,
	orders,
	lineitem,
	nation
where
	c_custkey = o_custkey
	and l_orderkey = o_orderkey
	and o_orderdate >= date '1993-09-01'
	and o_orderdate < cast(date '1993-09-01' + interval '3 month' as date)
	and l_returnflag = 'R'
	and c_nationkey = n_nationkey
group by
	c_custkey,
	c_name,
	c_acctbal,
	c_phone,
	n_name,
	c_address,
	c_comment
order by
	revenue desc
LIMIT 20;
                                                                                               QUERY PLAN                                                                                                
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Limit  (cost=2272567.94..2272567.99 rows=20 width=176) (actual time=32927.024..32927.031 rows=20 loops=1)
   Buffers: shared hit=1148798 read=206490 dirtied=253 written=3
   ->  Sort  (cost=2272567.94..2273960.78 rows=557136 width=176) (actual time=32927.021..32927.024 rows=20 loops=1)
         Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount))))
         Sort Method: top-N heapsort  Memory: 30kB
         Buffers: shared hit=1148798 read=206490 dirtied=253 written=3
         ->  HashAggregate  (cost=2252171.39..2257742.75 rows=557136 width=176) (actual time=32593.753..32790.562 rows=378492 loops=1)
               Group Key: customer.c_custkey, customer.c_name, customer.c_acctbal, customer.c_phone, nation.n_name, customer.c_address, customer.c_comment
               Buffers: shared hit=1148795 read=206490 dirtied=253 written=3
               ->  Hash Join  (cost=343816.65..2238242.99 rows=557136 width=176) (actual time=10187.752..30718.309 rows=1135202 loops=1)
                     Hash Cond: (customer.c_nationkey = nation.n_nationkey)
                     Buffers: shared hit=1148795 read=206490 dirtied=253 written=3
                     ->  Hash Join  (cost=343815.09..2230580.81 rows=557136 width=154) (actual time=10187.725..30330.075 rows=1135202 loops=1)
                           Hash Cond: (orders.o_custkey = customer.c_custkey)
                           Buffers: shared hit=1148794 read=206490 dirtied=253 written=3
                           ->  Hash Join  (cost=274787.09..2153195.77 rows=557136 width=12) (actual time=8812.059..28146.491 rows=1135202 loops=1)
                                 Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
                                 Buffers: shared hit=1113577 read=206429 dirtied=253 written=3
                                 ->  Seq Scan on lineitem  (cost=0.00..1817043.65 rows=14878312 width=12) (actual time=0.010..16259.097 rows=14808323 loops=1)
                                       Filter: (l_returnflag = 'R'::bpchar)
                                       Rows Removed by Filter: 45177006
                                       Buffers: shared hit=988581 read=77892
                                 ->  Hash  (cost=267758.91..267758.91 rows=562254 width=8) (actual time=8807.463..8807.463 rows=567322 loops=1)
                                       Buckets: 1048576  Batches: 1  Memory Usage: 30354kB
                                       Buffers: shared hit=124996 read=128537 dirtied=253 written=3
                                       ->  Bitmap Heap Scan on orders  (cost=5803.10..267758.91 rows=562254 width=8) (actual time=27.435..8564.593 rows=567322 loops=1)
                                             Recheck Cond: ((o_orderdate >= '1993-09-01'::date) AND (o_orderdate < '1993-12-01'::date))
                                             Rows Removed by Index Recheck: 14432678
                                             Heap Blocks: lossy=253522
                                             Buffers: shared hit=124996 read=128537 dirtied=253 written=3
                                             ->  Bitmap Index Scan on orders_o_orderkey_o_orderdate_brin_idx  (cost=0.00..5662.54 rows=562254 width=0) (actual time=27.265..27.265 rows=2535680 loops=1)
                                                   Index Cond: ((o_orderdate >= '1993-09-01'::date) AND (o_orderdate < '1993-12-01'::date))
                                                   Buffers: shared hit=2 read=9
                           ->  Hash  (cost=50278.00..50278.00 rows=1500000 width=146) (actual time=1366.885..1366.885 rows=1500000 loops=1)
                                 Buckets: 2097152  Batches: 1  Memory Usage: 281501kB
                                 Buffers: shared hit=35217 read=61
                                 ->  Seq Scan on customer  (cost=0.00..50278.00 rows=1500000 width=146) (actual time=0.009..541.325 rows=1500000 loops=1)
                                       Buffers: shared hit=35217 read=61
                     ->  Hash  (cost=1.25..1.25 rows=25 width=30) (actual time=0.017..0.017 rows=25 loops=1)
                           Buckets: 1024  Batches: 1  Memory Usage: 10kB
                           Buffers: shared hit=1
                           ->  Seq Scan on nation  (cost=0.00..1.25 rows=25 width=30) (actual time=0.004..0.008 rows=25 loops=1)
                                 Buffers: shared hit=1
 Planning time: 2.948 ms
 Execution time: 32939.258 ms
(45 rows)

COMMIT;
COMMIT