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 '1993-01-01'
	and l_shipdate < cast(date '1993-01-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1169473.07..1169473.09 rows=1 width=29) (actual time=7130.516..7130.516 rows=1 loops=1)
   Buffers: shared hit=220776 read=234842 dirtied=160
   ->  Hash Join  (cost=102009.80..1155863.65 rows=777681 width=29) (actual time=2090.012..6747.972 rows=773998 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=220776 read=234842 dirtied=160
         ->  Bitmap Heap Scan on lineitem  (cost=16487.80..1058676.44 rows=777681 width=12) (actual time=492.455..4347.690 rows=773998 loops=1)
               Recheck Cond: ((l_shipdate >= '1993-01-01'::date) AND (l_shipdate < '1993-02-01'::date))
               Heap Blocks: exact=412976
               Buffers: shared hit=219098 read=195995 dirtied=160
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..16293.38 rows=777681 width=0) (actual time=324.553..324.553 rows=774742 loops=1)
                     Index Cond: ((l_shipdate >= '1993-01-01'::date) AND (l_shipdate < '1993-02-01'::date))
                     Buffers: shared hit=1 read=2116
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=1581.246..1581.246 rows=2000000 loops=1)
               Buckets: 2097152  Batches: 1  Memory Usage: 131903kB
               Buffers: shared hit=1675 read=38847
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.015..909.019 rows=2000000 loops=1)
                     Buffers: shared hit=1675 read=38847
 Planning time: 2.675 ms
 Execution time: 7139.603 ms
(19 rows)

COMMIT;
COMMIT