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 '1996-04-01'
	and l_shipdate < cast(date '1996-04-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1162572.88..1162572.89 rows=1 width=29) (actual time=9277.557..9277.558 rows=1 loops=1)
   Buffers: shared hit=181005 read=268242 dirtied=172 written=4596
   ->  Hash Join  (cost=101581.49..1149298.62 rows=758529 width=29) (actual time=2613.080..8889.120 rows=747550 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=181005 read=268242 dirtied=172 written=4596
         ->  Bitmap Heap Scan on lineitem  (cost=16059.49..1052398.69 rows=758529 width=12) (actual time=651.799..5639.206 rows=747550 loops=1)
               Recheck Cond: ((l_shipdate >= '1996-04-01'::date) AND (l_shipdate < '1996-05-01'::date))
               Heap Blocks: exact=406676
               Buffers: shared hit=180995 read=227727 dirtied=172 written=1670
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..15869.86 rows=758529 width=0) (actual time=426.673..426.673 rows=751034 loops=1)
                     Index Cond: ((l_shipdate >= '1996-04-01'::date) AND (l_shipdate < '1996-05-01'::date))
                     Buffers: shared hit=162 read=1884 written=132
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=1948.754..1948.754 rows=2000000 loops=1)
               Buckets: 2097152  Batches: 1  Memory Usage: 131903kB
               Buffers: shared hit=7 read=40515 written=2926
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.016..1151.866 rows=2000000 loops=1)
                     Buffers: shared hit=7 read=40515 written=2926
 Planning time: 3.655 ms
 Execution time: 9283.177 ms
(19 rows)

COMMIT;
COMMIT