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 '1997-07-01'
	and l_shipdate < cast(date '1997-07-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1190343.29..1190343.30 rows=1 width=29) (actual time=6122.023..6122.023 rows=1 loops=1)
   Buffers: shared hit=360627 read=95098 dirtied=176 written=14
   ->  Hash Join  (cost=103049.04..1175874.67 rows=826778 width=29) (actual time=1899.658..5734.518 rows=774574 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=360627 read=95098 dirtied=176 written=14
         ->  Bitmap Heap Scan on lineitem  (cost=17527.04..1077951.00 rows=826778 width=12) (actual time=494.028..3631.959 rows=774574 loops=1)
               Recheck Cond: ((l_shipdate >= '1997-07-01'::date) AND (l_shipdate < '1997-08-01'::date))
               Heap Blocks: exact=413082
               Buffers: shared hit=320102 read=95098 dirtied=176 written=14
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..17320.34 rows=826778 width=0) (actual time=338.633..338.633 rows=775339 loops=1)
                     Index Cond: ((l_shipdate >= '1997-07-01'::date) AND (l_shipdate < '1997-08-01'::date))
                     Buffers: shared hit=2 read=2116
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=1394.279..1394.279 rows=2000000 loops=1)
               Buckets: 2097152  Batches: 1  Memory Usage: 131903kB
               Buffers: shared hit=40522
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.019..728.657 rows=2000000 loops=1)
                     Buffers: shared hit=40522
 Planning time: 2.923 ms
 Execution time: 6124.656 ms
(19 rows)

COMMIT;
COMMIT