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 '1995-05-01'
	and l_shipdate < cast(date '1995-05-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1188337.99..1188338.01 rows=1 width=29) (actual time=21513.462..21513.463 rows=1 loops=1)
   Buffers: shared hit=212398 read=246780 dirtied=414 written=2948
   ->  Hash Join  (cost=102198.09..1174506.57 rows=790367 width=29) (actual time=4715.245..20797.929 rows=773283 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=212398 read=246780 dirtied=414 written=2948
         ->  Bitmap Heap Scan on lineitem  (cost=16676.09..1071201.31 rows=790367 width=12) (actual time=994.154..13185.003 rows=773283 loops=1)
               Recheck Cond: ((l_shipdate >= '1995-05-01'::date) AND (l_shipdate < '1995-06-01'::date))
               Buffers: shared hit=212393 read=206260 dirtied=414 written=2942
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..16478.50 rows=790367 width=0) (actual time=763.156..763.156 rows=781873 loops=1)
                     Index Cond: ((l_shipdate >= '1995-05-01'::date) AND (l_shipdate < '1995-06-01'::date))
                     Buffers: shared hit=3 read=2114 written=73
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=3719.509..3719.509 rows=2000000 loops=1)
               Buckets: 262144  Batches: 1  Memory Usage: 115519kB
               Buffers: shared hit=2 read=40520 written=6
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.009..2155.875 rows=2000000 loops=1)
                     Buffers: shared hit=2 read=40520 written=6
 Total runtime: 21543.326 ms
(17 rows)

COMMIT;
COMMIT