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=1139865.26..1139865.28 rows=1 width=29) (actual time=8136.183..8136.183 rows=1 loops=1)
   Buffers: shared hit=176325 read=258845 written=263
   ->  Hash Join  (cost=100544.96..1127431.90 rows=710478 width=29) (actual time=2292.185..7767.854 rows=698931 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=176325 read=258845 written=263
         ->  Bitmap Heap Scan on lineitem  (cost=15022.96..1031252.73 rows=710478 width=12) (actual time=555.643..5361.049 rows=698931 loops=1)
               Recheck Cond: ((l_shipdate >= '1994-02-01'::date) AND (l_shipdate < '1994-03-01'::date))
               Heap Blocks: exact=392733
               Buffers: shared hit=174776 read=219869 written=257
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..14845.34 rows=710478 width=0) (actual time=366.529..366.529 rows=703103 loops=1)
                     Index Cond: ((l_shipdate >= '1994-02-01'::date) AND (l_shipdate < '1994-03-01'::date))
                     Buffers: shared read=1912
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=1725.166..1725.166 rows=2000000 loops=1)
               Buckets: 2097152  Batches: 1  Memory Usage: 131903kB
               Buffers: shared hit=1546 read=38976 written=6
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.013..1026.316 rows=2000000 loops=1)
                     Buffers: shared hit=1546 read=38976 written=6
 Planning time: 4.162 ms
 Execution time: 8139.992 ms
(19 rows)

COMMIT;
COMMIT