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 '1993-03-01'
	and l_shipdate < cast(date '1993-03-01' + interval '1 month' as date);
                                                                               QUERY PLAN                                                                                
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=1169202.02..1169202.03 rows=1 width=29) (actual time=8695.053..8695.054 rows=1 loops=1)
   Buffers: shared hit=216366 read=241591 dirtied=63 written=6370
   ->  Hash Join  (cost=101819.13..1155720.07 rows=770397 width=29) (actual time=2635.677..8289.923 rows=774351 loops=1)
         Hash Cond: (lineitem.l_partkey = part.p_partkey)
         Buffers: shared hit=216366 read=241591 dirtied=63 written=6370
         ->  Bitmap Heap Scan on lineitem  (cost=16297.13..1058642.11 rows=770397 width=12) (actual time=607.984..5397.539 rows=774351 loops=1)
               Recheck Cond: ((l_shipdate >= '1993-03-01'::date) AND (l_shipdate < '1993-04-01'::date))
               Heap Blocks: exact=415313
               Buffers: shared hit=207810 read=209622 dirtied=63 written=4697
               ->  Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx  (cost=0.00..16104.54 rows=770397 width=0) (actual time=430.864..430.864 rows=779068 loops=1)
                     Index Cond: ((l_shipdate >= '1993-03-01'::date) AND (l_shipdate < '1993-04-01'::date))
                     Buffers: shared hit=105 read=2014 written=78
         ->  Hash  (cost=60522.00..60522.00 rows=2000000 width=25) (actual time=2014.559..2014.559 rows=2000000 loops=1)
               Buckets: 2097152  Batches: 1  Memory Usage: 131903kB
               Buffers: shared hit=8553 read=31969 written=1673
               ->  Seq Scan on part  (cost=0.00..60522.00 rows=2000000 width=25) (actual time=0.018..1142.512 rows=2000000 loops=1)
                     Buffers: shared hit=8553 read=31969 written=1673
 Planning time: 4.270 ms
 Execution time: 8698.157 ms
(19 rows)

COMMIT;
COMMIT