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 '1995-02-01'
	and l_shipdate < cast(date '1995-02-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1139991.61..1139991.63 rows=1 width=29) (actual time=9770.945..9770.945 rows=1 loops=1)
   Buffers: shared hit=117952 read=318056 dirtied=103 written=25497
   ->  Hash Join  (cost=100278.24..1127771.64 rows=698284 width=29) (actual time=2028.680..9391.497 rows=697507 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=117952 read=318056 dirtied=103 written=25497
         ->  Bitmap Heap Scan on lineitem  (cost=14756.24..1026538.25 rows=698284 width=12) (actual time=566.424..5809.040 rows=697507 loops=1)
               Recheck Cond: ((l_shipdate >= '1995-02-01'::date) AND (l_shipdate < '1995-03-01'::date))
               Buffers: shared hit=77430 read=318053 dirtied=103 written=25497
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..14581.67 rows=698284 width=0) (actual time=369.775..369.775 rows=703913 loops=1)
                     Index Cond: ((l_shipdate >= '1995-02-01'::date) AND (l_shipdate < '1995-03-01'::date))
                     Buffers: shared hit=191 read=1720
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=1460.516..1460.516 rows=2000000 loops=1)
               Buckets: 262144  Batches: 1  Memory Usage: 115519kB
               Buffers: shared hit=40519 read=3
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.013..754.382 rows=2000000 loops=1)
                     Buffers: shared hit=40519 read=3
 Total runtime: 9784.822 ms
(17 rows)

COMMIT;
COMMIT