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 '1995-12-01'
	and l_shipdate < cast(date '1995-12-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1180232.68..1180232.70 rows=1 width=29) (actual time=13032.365..13032.366 rows=1 loops=1)
   Buffers: shared hit=167062 read=292288 dirtied=287 written=1422
   ->  Hash Join  (cost=101747.86..1166760.18 rows=769857 width=29) (actual time=2914.202..12433.131 rows=772407 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=167062 read=292288 dirtied=287 written=1422
         ->  Bitmap Heap Scan on lineitem  (cost=16225.86..1063916.40 rows=769857 width=12) (actual time=727.976..7642.534 rows=772407 loops=1)
               Recheck Cond: ((l_shipdate >= '1995-12-01'::date) AND (l_shipdate < '1996-01-01'::date))
               Buffers: shared hit=149780 read=269045 dirtied=287 written=1161
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..16033.40 rows=769857 width=0) (actual time=527.971..527.971 rows=782561 loops=1)
                     Index Cond: ((l_shipdate >= '1995-12-01'::date) AND (l_shipdate < '1996-01-01'::date))
                     Buffers: shared hit=7 read=2106 written=39
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=2184.287..2184.287 rows=2000000 loops=1)
               Buckets: 262144  Batches: 1  Memory Usage: 115519kB
               Buffers: shared hit=17279 read=23243 written=261
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.015..1212.930 rows=2000000 loops=1)
                     Buffers: shared hit=17279 read=23243 written=261
 Total runtime: 13044.185 ms
(17 rows)

COMMIT;
COMMIT