BEGIN; BEGIN EXPLAIN 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 '1993-09-01' and l_shipdate < cast(date '1993-09-01' + interval '1 month' as date); QUERY PLAN ---------------------------------------------------------------------------------------------------------------------- Aggregate (cost=1168510.81..1168510.82 rows=1 width=29) -> Hash Join (cost=101746.19..1155129.94 rows=764621 width=29) Hash Cond: (lineitem.l_partkey = part.p_partkey) -> Bitmap Heap Scan on lineitem (cost=16224.19..1052403.97 rows=764621 width=12) Recheck Cond: ((l_shipdate >= '1993-09-01'::date) AND (l_shipdate < '1993-10-01'::date)) -> Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx (cost=0.00..16033.04 rows=764621 width=0) Index Cond: ((l_shipdate >= '1993-09-01'::date) AND (l_shipdate < '1993-10-01'::date)) -> Hash (cost=60522.00..60522.00 rows=2000000 width=25) -> Seq Scan on part (cost=0.00..60522.00 rows=2000000 width=25) (9 rows) COMMIT; COMMIT