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 '1994-04-01'
	and l_shipdate < cast(date '1994-04-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1164907.77..1164907.79 rows=1 width=29) (actual time=7959.135..7959.135 rows=1 loops=1)
   Buffers: shared hit=133481 read=318712 dirtied=416 written=108
   ->  Hash Join  (cost=101360.61..1151757.94 rows=751419 width=29) (actual time=2231.196..7591.068 rows=746815 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=133481 read=318712 dirtied=416 written=108
         ->  Bitmap Heap Scan on lineitem  (cost=15838.61..1054964.65 rows=751419 width=12) (actual time=499.887..4791.866 rows=746815 loops=1)
               Recheck Cond: ((l_shipdate >= '1994-04-01'::date) AND (l_shipdate < '1994-05-01'::date))
               Heap Blocks: exact=409623
               Buffers: shared hit=133400 read=278268 dirtied=416 written=108
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..15650.76 rows=751419 width=0) (actual time=329.510..329.510 rows=756518 loops=1)
                     Index Cond: ((l_shipdate >= '1994-04-01'::date) AND (l_shipdate < '1994-05-01'::date))
                     Buffers: shared read=2045
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=1716.798..1716.798 rows=2000000 loops=1)
               Buckets: 2097152  Batches: 1  Memory Usage: 131903kB
               Buffers: shared hit=78 read=40444
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.015..929.781 rows=2000000 loops=1)
                     Buffers: shared hit=78 read=40444
 Planning time: 3.265 ms
 Execution time: 7963.767 ms
(19 rows)

COMMIT;
COMMIT