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 '1996-07-01'
	and l_shipdate < cast(date '1996-07-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1186653.19..1186653.20 rows=1 width=29) (actual time=19174.689..19174.689 rows=1 loops=1)
   Buffers: shared hit=164324 read=293763 written=58
   ->  Hash Join  (cost=102205.08..1172830.32 rows=789878 width=29) (actual time=3917.747..18461.344 rows=772783 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=164324 read=293763 written=58
         ->  Bitmap Heap Scan on lineitem  (cost=16683.08..1069536.07 rows=789878 width=12) (actual time=957.439..12544.077 rows=772783 loops=1)
               Recheck Cond: ((l_shipdate >= '1996-07-01'::date) AND (l_shipdate < '1996-08-01'::date))
               Buffers: shared hit=151886 read=265676 written=58
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..16485.61 rows=789878 width=0) (actual time=699.440..699.440 rows=779536 loops=1)
                     Index Cond: ((l_shipdate >= '1996-07-01'::date) AND (l_shipdate < '1996-08-01'::date))
                     Buffers: shared hit=292 read=1821
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=2958.073..2958.073 rows=2000000 loops=1)
               Buckets: 262144  Batches: 1  Memory Usage: 115519kB
               Buffers: shared hit=12435 read=28087
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.015..1829.743 rows=2000000 loops=1)
                     Buffers: shared hit=12435 read=28087
 Total runtime: 19190.715 ms
(17 rows)

COMMIT;
COMMIT