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=1180020.55..1180020.57 rows=1 width=29) (actual time=7231.865..7231.865 rows=1 loops=1)
   Buffers: shared hit=245356 read=211993 dirtied=198 written=69
   ->  Hash Join  (cost=102338.40..1166109.61 rows=794911 width=29) (actual time=2254.576..6825.164 rows=775344 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=245356 read=211993 dirtied=198 written=69
         ->  Bitmap Heap Scan on lineitem  (cost=16816.40..1068663.94 rows=794911 width=12) (actual time=462.972..4198.229 rows=775344 loops=1)
               Recheck Cond: ((l_shipdate >= '1995-03-01'::date) AND (l_shipdate < '1995-04-01'::date))
               Heap Blocks: exact=414704
               Buffers: shared hit=245352 read=171472 dirtied=198 written=60
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..16617.67 rows=794911 width=0) (actual time=310.403..310.403 rows=779193 loops=1)
                     Index Cond: ((l_shipdate >= '1995-03-01'::date) AND (l_shipdate < '1995-04-01'::date))
                     Buffers: shared read=2120 written=7
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=1776.444..1776.444 rows=2000000 loops=1)
               Buckets: 2097152  Batches: 1  Memory Usage: 131903kB
               Buffers: shared hit=1 read=40521 written=9
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.008..955.856 rows=2000000 loops=1)
                     Buffers: shared hit=1 read=40521 written=9
 Planning time: 3.524 ms
 Execution time: 7358.330 ms
(19 rows)

COMMIT;
COMMIT