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 '1996-05-01'
	and l_shipdate < cast(date '1996-05-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1168121.51..1168121.52 rows=1 width=29) (actual time=45558.877..45558.877 rows=1 loops=1)
   Buffers: shared hit=142310 read=318007 dirtied=163 written=11482
   ->  Hash Join  (cost=101192.69..1155105.16 rows=743791 width=29) (actual time=6243.707..44744.954 rows=773103 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=142310 read=318007 dirtied=163 written=11482
         ->  Bitmap Heap Scan on lineitem  (cost=15670.69..1052847.87 rows=743791 width=12) (actual time=978.474..35955.840 rows=773103 loops=1)
               Recheck Cond: ((l_shipdate >= '1996-05-01'::date) AND (l_shipdate < '1996-06-01'::date))
               Buffers: shared hit=137633 read=282159 dirtied=163 written=11463
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..15484.74 rows=743791 width=0) (actual time=775.328..775.328 rows=784418 loops=1)
                     Index Cond: ((l_shipdate >= '1996-05-01'::date) AND (l_shipdate < '1996-06-01'::date))
                     Buffers: shared hit=37 read=2080
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=5263.115..5263.115 rows=2000000 loops=1)
               Buckets: 262144  Batches: 1  Memory Usage: 115519kB
               Buffers: shared hit=4674 read=35848 written=19
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.013..4042.921 rows=2000000 loops=1)
                     Buffers: shared hit=4674 read=35848 written=19
 Total runtime: 45574.265 ms
(17 rows)

COMMIT;
COMMIT