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 '1997-05-01'
	and l_shipdate < cast(date '1997-05-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1180817.47..1180817.49 rows=1 width=29) (actual time=38546.286..38546.286 rows=1 loops=1)
   Buffers: shared hit=210345 read=246920 written=6
   ->  Hash Join  (cost=102143.03..1167080.06 rows=784995 width=29) (actual time=5926.890..37748.002 rows=774601 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=210345 read=246920 written=6
         ->  Bitmap Heap Scan on lineitem  (cost=16621.03..1063895.67 rows=784995 width=12) (actual time=1133.969..28754.764 rows=774601 loops=1)
               Recheck Cond: ((l_shipdate >= '1997-05-01'::date) AND (l_shipdate < '1997-06-01'::date))
               Buffers: shared hit=179918 read=236822 written=6
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..16424.78 rows=784995 width=0) (actual time=848.492..848.492 rows=777699 loops=1)
                     Index Cond: ((l_shipdate >= '1997-05-01'::date) AND (l_shipdate < '1997-06-01'::date))
                     Buffers: shared read=2119
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=4790.531..4790.531 rows=2000000 loops=1)
               Buckets: 262144  Batches: 1  Memory Usage: 115519kB
               Buffers: shared hit=30424 read=10098
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.863..2743.490 rows=2000000 loops=1)
                     Buffers: shared hit=30424 read=10098
 Total runtime: 38580.866 ms
(17 rows)

COMMIT;
COMMIT