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 '1994-02-01'
	and l_shipdate < cast(date '1994-02-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1148862.81..1148862.83 rows=1 width=29) (actual time=10410.452..10410.453 rows=1 loops=1)
   Buffers: shared hit=229614 read=207147 written=75
   ->  Hash Join  (cost=100562.34..1136396.81 rows=712343 width=29) (actual time=2570.756..9935.180 rows=698999 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=229614 read=207147 written=75
         ->  Bitmap Heap Scan on lineitem  (cost=15040.34..1034847.09 rows=712343 width=12) (actual time=645.532..5698.697 rows=698999 loops=1)
               Recheck Cond: ((l_shipdate >= '1994-02-01'::date) AND (l_shipdate < '1994-03-01'::date))
               Buffers: shared hit=189093 read=207143 written=75
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..14862.26 rows=712343 width=0) (actual time=441.668..441.668 rows=705956 loops=1)
                     Index Cond: ((l_shipdate >= '1994-02-01'::date) AND (l_shipdate < '1994-03-01'::date))
                     Buffers: shared read=1913
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=1923.190..1923.190 rows=2000000 loops=1)
               Buckets: 262144  Batches: 1  Memory Usage: 115519kB
               Buffers: shared hit=40518 read=4
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.019..1001.749 rows=2000000 loops=1)
                     Buffers: shared hit=40518 read=4
 Total runtime: 10423.895 ms
(17 rows)

COMMIT;
COMMIT