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 '1996-08-01'
	and l_shipdate < cast(date '1996-08-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1170427.67..1170427.69 rows=1 width=29) (actual time=9358.070..9358.071 rows=1 loops=1)
   Buffers: shared hit=231473 read=224339 dirtied=458 written=8155
   ->  Hash Join  (cost=101958.58..1156844.23 rows=776197 width=29) (actual time=2786.165..8921.289 rows=772326 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=231473 read=224339 dirtied=458 written=8155
         ->  Bitmap Heap Scan on lineitem  (cost=16436.58..1059679.27 rows=776197 width=12) (actual time=673.447..5428.332 rows=772326 loops=1)
               Recheck Cond: ((l_shipdate >= '1996-08-01'::date) AND (l_shipdate < '1996-09-01'::date))
               Heap Blocks: exact=413172
               Buffers: shared hit=231468 read=183819 dirtied=458 written=6273
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..16242.54 rows=776197 width=0) (actual time=432.657..432.657 rows=775610 loops=1)
                     Index Cond: ((l_shipdate >= '1996-08-01'::date) AND (l_shipdate < '1996-09-01'::date))
                     Buffers: shared hit=117 read=1998 written=104
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=2088.300..2088.300 rows=2000000 loops=1)
               Buckets: 2097152  Batches: 1  Memory Usage: 131903kB
               Buffers: shared hit=2 read=40520 written=1882
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.010..1122.238 rows=2000000 loops=1)
                     Buffers: shared hit=2 read=40520 written=1882
 Planning time: 4.518 ms
 Execution time: 9367.318 ms
(19 rows)

COMMIT;
COMMIT