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=1165843.98..1165843.99 rows=1 width=29) (actual time=6808.212..6808.213 rows=1 loops=1)
   Buffers: shared hit=286780 read=169573 dirtied=232 written=57
   ->  Hash Join  (cost=101716.88..1152454.66 rows=765104 width=29) (actual time=2190.869..6417.339 rows=773568 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=286780 read=169573 dirtied=232 written=57
         ->  Bitmap Heap Scan on lineitem  (cost=16194.88..1055456.10 rows=765104 width=12) (actual time=566.175..4107.140 rows=773568 loops=1)
               Recheck Cond: ((l_shipdate >= '1995-05-01'::date) AND (l_shipdate < '1995-06-01'::date))
               Heap Blocks: exact=413712
               Buffers: shared hit=285422 read=130406 dirtied=232 written=21
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..16003.61 rows=765104 width=0) (actual time=379.646..379.646 rows=776652 loops=1)
                     Index Cond: ((l_shipdate >= '1995-05-01'::date) AND (l_shipdate < '1995-06-01'::date))
                     Buffers: shared hit=2 read=2114 written=16
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=1612.405..1612.405 rows=2000000 loops=1)
               Buckets: 2097152  Batches: 1  Memory Usage: 131903kB
               Buffers: shared hit=1355 read=39167 written=36
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.017..948.202 rows=2000000 loops=1)
                     Buffers: shared hit=1355 read=39167 written=36
 Planning time: 2.758 ms
 Execution time: 6814.481 ms
(19 rows)

COMMIT;
COMMIT