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 '1995-07-01'
	and l_shipdate < cast(date '1995-07-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1182428.85..1182428.87 rows=1 width=29) (actual time=42891.790..42891.790 rows=1 loops=1)
   Buffers: shared hit=166268 read=294488 dirtied=403 written=3874
   ->  Hash Join  (cost=101807.84..1168901.75 rows=772977 width=29) (actual time=6796.181..42099.216 rows=773729 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=166268 read=294488 dirtied=403 written=3874
         ->  Bitmap Heap Scan on lineitem  (cost=16285.84..1065987.77 rows=772977 width=12) (actual time=1214.657..33093.369 rows=773729 loops=1)
               Recheck Cond: ((l_shipdate >= '1995-07-01'::date) AND (l_shipdate < '1995-08-01'::date))
               Buffers: shared hit=160087 read=260144 dirtied=403 written=3874
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..16092.60 rows=772977 width=0) (actual time=953.410..953.410 rows=784396 loops=1)
                     Index Cond: ((l_shipdate >= '1995-07-01'::date) AND (l_shipdate < '1995-08-01'::date))
                     Buffers: shared read=2117
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=5579.546..5579.546 rows=2000000 loops=1)
               Buckets: 262144  Batches: 1  Memory Usage: 115519kB
               Buffers: shared hit=6178 read=34344
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.015..4404.611 rows=2000000 loops=1)
                     Buffers: shared hit=6178 read=34344
 Total runtime: 42907.363 ms
(17 rows)

COMMIT;
COMMIT