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 '1995-03-28'
	and l_shipdate > date '1995-03-28'
group by
	l_orderkey,
	o_orderdate,
	o_shippriority
order by
	revenue desc,
	o_orderdate
LIMIT 10;
                                                                                             QUERY PLAN                                                                                              
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Limit  (cost=2689638.98..2689639.00 rows=10 width=20) (actual time=33848.696..33848.700 rows=10 loops=1)
   Buffers: shared hit=710445 read=656515 written=176
   ->  Sort  (cost=2689638.98..2697622.44 rows=3193384 width=20) (actual time=33848.692..33848.693 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=710445 read=656515 written=176
         ->  HashAggregate  (cost=2588697.26..2620631.10 rows=3193384 width=20) (actual time=33772.368..33827.093 rows=113491 loops=1)
               Group Key: lineitem.l_orderkey, orders.o_orderdate, orders.o_shippriority
               Buffers: shared hit=710439 read=656515 written=176
               ->  Hash Join  (cost=556018.64..2540796.50 rows=3193384 width=20) (actual time=9116.666..33510.474 rows=300315 loops=1)
                     Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
                     Buffers: shared hit=710439 read=656515 written=176
                     ->  Seq Scan on lineitem  (cost=0.00..1831531.31 rows=32350055 width=12) (actual time=0.033..18381.941 rows=32038740 loops=1)
                           Filter: (l_shipdate > '1995-03-28'::date)
                           Rows Removed by Filter: 28005342
                           Buffers: shared hit=541908 read=533068 written=17
                     ->  Hash  (cost=537343.33..537343.33 rows=1494025 width=12) (actual time=9105.388..9105.388 rows=1475289 loops=1)
                           Buckets: 2097152  Batches: 1  Memory Usage: 79776kB
                           Buffers: shared hit=168531 read=123447 written=159
                           ->  Hash Join  (cost=49803.99..537343.33 rows=1494025 width=12) (actual time=835.510..8550.314 rows=1475289 loops=1)
                                 Hash Cond: (orders.o_custkey = customer.c_custkey)
                                 Buffers: shared hit=168531 read=123447 written=159
                                 ->  Seq Scan on orders  (cost=0.00..444735.19 rows=7430373 width=16) (actual time=0.024..5213.420 rows=7378191 loops=1)
                                       Filter: (o_orderdate < '1995-03-28'::date)
                                       Rows Removed by Filter: 7636809
                                       Buffers: shared hit=168529 read=87019 written=76
                                 ->  Hash  (cost=46033.93..46033.93 rows=301605 width=4) (actual time=832.305..832.305 rows=300441 loops=1)
                                       Buckets: 524288  Batches: 1  Memory Usage: 14659kB
                                       Buffers: shared hit=2 read=36428 written=83
                                       ->  Bitmap Heap Scan on customer  (cost=6985.87..46033.93 rows=301605 width=4) (actual time=78.789..733.950 rows=300441 loops=1)
                                             Recheck Cond: (c_mktsegment = 'MACHINERY'::bpchar)
                                             Heap Blocks: exact=35276
                                             Buffers: shared hit=2 read=36428 written=83
                                             ->  Bitmap Index Scan on customer_c_mktsegment_c_custkey_idx  (cost=0.00..6910.47 rows=301605 width=0) (actual time=69.112..69.112 rows=300441 loops=1)
                                                   Index Cond: (c_mktsegment = 'MACHINERY'::bpchar)
                                                   Buffers: shared read=1154
 Planning time: 4.398 ms
 Execution time: 33873.979 ms
(38 rows)

COMMIT;
COMMIT