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 '1995-11-01'
	and l_shipdate < cast(date '1995-11-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1167361.54..1167361.56 rows=1 width=29) (actual time=8091.921..8091.922 rows=1 loops=1)
   Buffers: shared hit=220697 read=230294 written=346
   ->  Hash Join  (cost=101585.36..1154046.53 rows=760858 width=29) (actual time=2599.683..7699.923 rows=748603 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=220697 read=230294 written=346
         ->  Bitmap Heap Scan on lineitem  (cost=16063.36..1057111.66 rows=760858 width=12) (actual time=773.059..5019.743 rows=748603 loops=1)
               Recheck Cond: ((l_shipdate >= '1995-11-01'::date) AND (l_shipdate < '1995-12-01'::date))
               Heap Blocks: exact=408419
               Buffers: shared hit=215861 read=194605 written=286
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..15873.15 rows=760858 width=0) (actual time=536.111..536.111 rows=755402 loops=1)
                     Index Cond: ((l_shipdate >= '1995-11-01'::date) AND (l_shipdate < '1995-12-01'::date))
                     Buffers: shared read=2047 written=3
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=1812.599..1812.599 rows=2000000 loops=1)
               Buckets: 2097152  Batches: 1  Memory Usage: 131903kB
               Buffers: shared hit=4833 read=35689 written=60
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.011..943.245 rows=2000000 loops=1)
                     Buffers: shared hit=4833 read=35689 written=60
 Planning time: 4.906 ms
 Execution time: 8095.181 ms
(19 rows)

COMMIT;
COMMIT