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 '1995-03-01'
	and l_shipdate < cast(date '1995-03-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1179593.38..1179593.40 rows=1 width=29) (actual time=7720.784..7720.784 rows=1 loops=1)
   Buffers: shared hit=164366 read=294548 dirtied=376 written=171
   ->  Hash Join  (cost=102144.85..1165814.84 rows=787345 width=29) (actual time=2198.598..7326.756 rows=775040 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=164366 read=294548 dirtied=376 written=171
         ->  Bitmap Heap Scan on lineitem  (cost=16622.85..1068482.67 rows=787345 width=12) (actual time=569.143..4951.978 rows=775040 loops=1)
               Recheck Cond: ((l_shipdate >= '1995-03-01'::date) AND (l_shipdate < '1995-04-01'::date))
               Heap Blocks: exact=416269
               Buffers: shared hit=162279 read=256110 dirtied=376 written=168
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..16426.01 rows=787345 width=0) (actual time=371.384..371.384 rows=782128 loops=1)
                     Index Cond: ((l_shipdate >= '1995-03-01'::date) AND (l_shipdate < '1995-04-01'::date))
                     Buffers: shared read=2120
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=1617.043..1617.043 rows=2000000 loops=1)
               Buckets: 2097152  Batches: 1  Memory Usage: 131903kB
               Buffers: shared hit=2084 read=38438 written=3
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.016..926.746 rows=2000000 loops=1)
                     Buffers: shared hit=2084 read=38438 written=3
 Planning time: 2.529 ms
 Execution time: 7725.597 ms
(19 rows)

COMMIT;
COMMIT