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 '1996-10-01'
	and l_shipdate < cast(date '1996-10-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1177805.40..1177805.41 rows=1 width=29) (actual time=15980.447..15980.447 rows=1 loops=1)
   Buffers: shared hit=307132 read=148077 dirtied=244 written=211
   ->  Hash Join  (cost=102132.16..1164100.20 rows=783154 width=29) (actual time=6463.256..15427.448 rows=773854 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=307132 read=148077 dirtied=244 written=211
         ->  Bitmap Heap Scan on lineitem  (cost=16610.16..1060957.24 rows=783154 width=12) (actual time=832.724..6259.655 rows=773854 loops=1)
               Recheck Cond: ((l_shipdate >= '1996-10-01'::date) AND (l_shipdate < '1996-11-01'::date))
               Buffers: shared hit=297824 read=116860 dirtied=244 written=211
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..16414.37 rows=783154 width=0) (actual time=617.127..617.127 rows=774616 loops=1)
                     Index Cond: ((l_shipdate >= '1996-10-01'::date) AND (l_shipdate < '1996-11-01'::date))
                     Buffers: shared hit=4 read=2113
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=5628.469..5628.469 rows=2000000 loops=1)
               Buckets: 262144  Batches: 1  Memory Usage: 115519kB
               Buffers: shared hit=9305 read=31217
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.019..1435.694 rows=2000000 loops=1)
                     Buffers: shared hit=9305 read=31217
 Total runtime: 16013.867 ms
(17 rows)

COMMIT;
COMMIT