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 '1997-04-01'
	and l_shipdate < cast(date '1997-04-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1162679.53..1162679.54 rows=1 width=29) (actual time=9105.388..9105.389 rows=1 loops=1)
   Buffers: shared hit=354326 read=95013 dirtied=394 written=294
   ->  Hash Join  (cost=101450.60..1149536.99 rows=751002 width=29) (actual time=2582.351..8673.864 rows=750680 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=354326 read=95013 dirtied=394 written=294
         ->  Bitmap Heap Scan on lineitem  (cost=15928.60..1047117.45 rows=751002 width=12) (actual time=622.650..4198.346 rows=750680 loops=1)
               Recheck Cond: ((l_shipdate >= '1997-04-01'::date) AND (l_shipdate < '1997-05-01'::date))
               Buffers: shared hit=313802 read=95012 dirtied=394 written=294
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..15740.85 rows=751002 width=0) (actual time=444.008..444.008 rows=751450 loops=1)
                     Index Cond: ((l_shipdate >= '1997-04-01'::date) AND (l_shipdate < '1997-05-01'::date))
                     Buffers: shared hit=6 read=2048
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=1957.541..1957.541 rows=2000000 loops=1)
               Buckets: 262144  Batches: 1  Memory Usage: 115519kB
               Buffers: shared hit=40521 read=1
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.013..979.546 rows=2000000 loops=1)
                     Buffers: shared hit=40521 read=1
 Total runtime: 9119.431 ms
(17 rows)

COMMIT;
COMMIT