BEGIN;
BEGIN
EXPLAIN (ANALYZE, BUFFERS)
select
	l_orderkey,
	sum(l_extendedprice * (1 - l_discount)) as revenue,
	o_orderdate,
	o_shippriority
from
	customer,
	orders,
	lineitem
where
	c_mktsegment = 'MACHINERY'
	and c_custkey = o_custkey
	and l_orderkey = o_orderkey
	and o_orderdate < date '1995-03-25'
	and l_shipdate > date '1995-03-25'
group by
	l_orderkey,
	o_orderdate,
	o_shippriority
order by
	revenue desc,
	o_orderdate
LIMIT 10;
                                                                                             QUERY PLAN                                                                                              
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Limit  (cost=2697476.13..2697476.15 rows=10 width=20) (actual time=32059.396..32059.399 rows=10 loops=1)
   Buffers: shared hit=967361 read=404897 written=47
   ->  Sort  (cost=2697476.13..2705387.05 rows=3164368 width=20) (actual time=32059.393..32059.394 rows=10 loops=1)
         Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))), orders.o_orderdate
         Sort Method: top-N heapsort  Memory: 25kB
         Buffers: shared hit=967361 read=404897 written=47
         ->  HashAggregate  (cost=2597451.59..2629095.27 rows=3164368 width=20) (actual time=31991.745..32038.609 rows=113582 loops=1)
               Group Key: lineitem.l_orderkey, orders.o_orderdate, orders.o_shippriority
               Buffers: shared hit=967355 read=404897 written=47
               ->  Hash Join  (cost=557154.80..2549986.08 rows=3164368 width=20) (actual time=8320.931..31731.170 rows=300665 loops=1)
                     Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
                     Buffers: shared hit=967355 read=404897 written=47
                     ->  Seq Scan on lineitem  (cost=0.00..1838832.43 rows=32628046 width=12) (actual time=0.028..17845.029 rows=32114835 loops=1)
                           Filter: (l_shipdate > '1995-03-25'::date)
                           Rows Removed by Filter: 27930462
                           Buffers: shared hit=712978 read=366284
                     ->  Hash  (cost=538734.19..538734.19 rows=1473649 width=12) (actual time=8307.974..8307.974 rows=1471743 loops=1)
                           Buckets: 2097152  Batches: 1  Memory Usage: 79623kB
                           Buffers: shared hit=254377 read=38613 written=47
                           ->  Hash Join  (cost=49575.77..538734.19 rows=1473649 width=12) (actual time=492.990..7759.412 rows=1471743 loops=1)
                                 Hash Cond: (orders.o_custkey = customer.c_custkey)
                                 Buffers: shared hit=254377 read=38613 written=47
                                 ->  Seq Scan on orders  (cost=0.00..446496.39 rows=7446809 width=16) (actual time=0.021..4720.600 rows=7359577 loops=1)
                                       Filter: (o_orderdate < '1995-03-25'::date)
                                       Rows Removed by Filter: 7655423
                                       Buffers: shared hit=219101 read=37459 written=47
                                 ->  Hash  (cost=45865.34..45865.34 rows=296835 width=4) (actual time=489.206..489.206 rows=300441 loops=1)
                                       Buckets: 524288  Batches: 1  Memory Usage: 14659kB
                                       Buffers: shared hit=35276 read=1154
                                       ->  Bitmap Heap Scan on customer  (cost=6876.90..45865.34 rows=296835 width=4) (actual time=77.729..402.732 rows=300441 loops=1)
                                             Recheck Cond: (c_mktsegment = 'MACHINERY'::bpchar)
                                             Heap Blocks: exact=35276
                                             Buffers: shared hit=35276 read=1154
                                             ->  Bitmap Index Scan on customer_c_mktsegment_c_custkey_idx  (cost=0.00..6802.69 rows=296835 width=0) (actual time=67.516..67.516 rows=300441 loops=1)
                                                   Index Cond: (c_mktsegment = 'MACHINERY'::bpchar)
                                                   Buffers: shared read=1154
 Planning time: 3.578 ms
 Execution time: 32089.585 ms
(38 rows)

COMMIT;
COMMIT