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 '1994-12-01'
	and l_shipdate < cast(date '1994-12-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1177264.84..1177264.86 rows=1 width=29) (actual time=7261.618..7261.618 rows=1 loops=1)
   Buffers: shared hit=198706 read=257369 dirtied=154 written=26
   ->  Hash Join  (cost=102382.72..1163346.53 rows=795332 width=29) (actual time=2123.521..6854.118 rows=774316 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=198706 read=257369 dirtied=154 written=26
         ->  Bitmap Heap Scan on lineitem  (cost=16860.72..1065894.55 rows=795332 width=12) (actual time=497.109..4480.370 rows=774316 loops=1)
               Recheck Cond: ((l_shipdate >= '1994-12-01'::date) AND (l_shipdate < '1995-01-01'::date))
               Heap Blocks: exact=413433
               Buffers: shared hit=196716 read=218834 dirtied=154 written=26
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..16661.88 rows=795332 width=0) (actual time=336.927..336.927 rows=775052 loops=1)
                     Index Cond: ((l_shipdate >= '1994-12-01'::date) AND (l_shipdate < '1995-01-01'::date))
                     Buffers: shared hit=2 read=2115
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=1618.478..1618.478 rows=2000000 loops=1)
               Buckets: 2097152  Batches: 1  Memory Usage: 131903kB
               Buffers: shared hit=1987 read=38535
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.012..931.768 rows=2000000 loops=1)
                     Buffers: shared hit=1987 read=38535
 Planning time: 3.115 ms
 Execution time: 7264.283 ms
(19 rows)

COMMIT;
COMMIT