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 '1995-03-27'
	and l_shipdate > date '1995-03-27'
group by
	l_orderkey,
	o_orderdate,
	o_shippriority
order by
	revenue desc,
	o_orderdate
LIMIT 10;
                                                                                             QUERY PLAN                                                                                              
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Limit  (cost=2668759.31..2668759.33 rows=10 width=20) (actual time=38104.410..38104.415 rows=10 loops=1)
   Buffers: shared hit=495982 read=861775 dirtied=253 written=20
   ->  Sort  (cost=2668759.31..2676588.28 rows=3131590 width=20) (actual time=38104.405..38104.408 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=495982 read=861775 dirtied=253 written=20
         ->  HashAggregate  (cost=2569770.87..2601086.77 rows=3131590 width=20) (actual time=38033.254..38082.475 rows=113553 loops=1)
               Group Key: lineitem.l_orderkey, orders.o_orderdate, orders.o_shippriority
               Buffers: shared hit=495976 read=861775 dirtied=253 written=20
               ->  Hash Join  (cost=551767.43..2522797.02 rows=3131590 width=20) (actual time=11296.209..37739.867 rows=300615 loops=1)
                     Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
                     Buffers: shared hit=495976 read=861775 dirtied=253 written=20
                     ->  Seq Scan on lineitem  (cost=0.00..1818870.86 rows=32224755 width=12) (actual time=0.032..19286.111 rows=32065594 loops=1)
                           Filter: (l_shipdate > '1995-03-27'::date)
                           Rows Removed by Filter: 27980009
                           Buffers: shared hit=344694 read=722852 written=1
                     ->  Hash  (cost=533509.84..533509.84 rows=1460607 width=12) (actual time=11280.163..11280.163 rows=1473997 loops=1)
                           Buckets: 2097152  Batches: 1  Memory Usage: 79720kB
                           Buffers: shared hit=151282 read=138923 dirtied=253 written=19
                           ->  Hash Join  (cost=49575.77..533509.84 rows=1460607 width=12) (actual time=846.116..10595.959 rows=1473997 loops=1)
                                 Hash Cond: (orders.o_custkey = customer.c_custkey)
                                 Buffers: shared hit=151282 read=138923 dirtied=253 written=19
                                 ->  Seq Scan on orders  (cost=0.00..441649.60 rows=7380906 width=16) (actual time=0.027..5389.639 rows=7371832 loops=1)
                                       Filter: (o_orderdate < '1995-03-27'::date)
                                       Rows Removed by Filter: 7643168
                                       Buffers: shared hit=151280 read=102495 dirtied=253 written=2
                                 ->  Hash  (cost=45865.34..45865.34 rows=296835 width=4) (actual time=842.555..842.555 rows=300441 loops=1)
                                       Buckets: 524288  Batches: 1  Memory Usage: 14659kB
                                       Buffers: shared hit=2 read=36428 written=17
                                       ->  Bitmap Heap Scan on customer  (cost=6876.90..45865.34 rows=296835 width=4) (actual time=82.442..734.953 rows=300441 loops=1)
                                             Recheck Cond: (c_mktsegment = 'MACHINERY'::bpchar)
                                             Heap Blocks: exact=35276
                                             Buffers: shared hit=2 read=36428 written=17
                                             ->  Bitmap Index Scan on customer_c_mktsegment_c_custkey_idx  (cost=0.00..6802.69 rows=296835 width=0) (actual time=73.188..73.188 rows=300441 loops=1)
                                                   Index Cond: (c_mktsegment = 'MACHINERY'::bpchar)
                                                   Buffers: shared read=1154
 Planning time: 4.660 ms
 Execution time: 38127.975 ms
(38 rows)

COMMIT;
COMMIT