BEGIN;
BEGIN
EXPLAIN (ANALYZE, BUFFERS)
select
	100.00 * sum(case
		when p_type like 'PROMO%'
			then l_extendedprice * (1 - l_discount)
		else 0
	end) / sum(l_extendedprice * (1 - l_discount)) as promo_revenue
from
	lineitem,
	part
where
	l_partkey = p_partkey
	and l_shipdate >= date '1997-01-01'
	and l_shipdate < cast(date '1997-01-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1176521.15..1176521.17 rows=1 width=29) (actual time=7253.525..7253.526 rows=1 loops=1)
   Buffers: shared hit=967 read=453571
   ->  Hash Join  (cost=102390.70..1162602.88 rows=795330 width=29) (actual time=1804.675..6861.890 rows=773251 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=967 read=453571
         ->  Bitmap Heap Scan on lineitem  (cost=16868.70..1065150.93 rows=795330 width=12) (actual time=397.927..4784.617 rows=773251 loops=1)
               Recheck Cond: ((l_shipdate >= '1997-01-01'::date) AND (l_shipdate < '1997-02-01'::date))
               Heap Blocks: exact=411898
               Buffers: shared hit=962 read=413051
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..16669.86 rows=795330 width=0) (actual time=248.547..248.547 rows=773251 loops=1)
                     Index Cond: ((l_shipdate >= '1997-01-01'::date) AND (l_shipdate < '1997-02-01'::date))
                     Buffers: shared hit=592 read=1523
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=1399.359..1399.359 rows=2000000 loops=1)
               Buckets: 2097152  Batches: 1  Memory Usage: 131903kB
               Buffers: shared hit=2 read=40520
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.015..759.399 rows=2000000 loops=1)
                     Buffers: shared hit=2 read=40520
 Planning time: 4.187 ms
 Execution time: 7256.444 ms
(19 rows)

COMMIT;
COMMIT