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 '1994-06-01'
	and l_shipdate < cast(date '1994-06-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1163948.10..1163948.11 rows=1 width=29) (actual time=8780.673..8780.673 rows=1 loops=1)
   Buffers: shared hit=137790 read=314889 written=73
   ->  Hash Join  (cost=101320.57..1150832.48 rows=749464 width=29) (actual time=2304.731..8383.090 rows=749246 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=137790 read=314889 written=73
         ->  Bitmap Heap Scan on lineitem  (cost=15798.57..1054068.52 rows=749464 width=12) (actual time=491.641..5763.040 rows=749246 loops=1)
               Recheck Cond: ((l_shipdate >= '1994-06-01'::date) AND (l_shipdate < '1994-07-01'::date))
               Heap Blocks: exact=410106
               Buffers: shared hit=137782 read=274372 written=35
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..15611.20 rows=749464 width=0) (actual time=333.453..333.453 rows=758174 loops=1)
                     Index Cond: ((l_shipdate >= '1994-06-01'::date) AND (l_shipdate < '1994-07-01'::date))
                     Buffers: shared read=2048 written=3
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=1800.934..1800.934 rows=2000000 loops=1)
               Buckets: 2097152  Batches: 1  Memory Usage: 131903kB
               Buffers: shared hit=5 read=40517 written=38
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.012..1005.262 rows=2000000 loops=1)
                     Buffers: shared hit=5 read=40517 written=38
 Planning time: 3.995 ms
 Execution time: 8782.666 ms
(19 rows)

COMMIT;
COMMIT