BEGIN; BEGIN EXPLAIN select sum(l_extendedprice) / 7.0 as avg_yearly from lineitem, part where p_partkey = l_partkey and p_brand = 'Brand#51' and p_container = 'JUMBO BOX' and l_quantity < ( select 0.2 * avg(l_quantity) from lineitem where l_partkey = p_partkey ); QUERY PLAN --------------------------------------------------------------------------------------------------------------------------------------------- Aggregate (cost=114855.77..114855.78 rows=1 width=4) -> Nested Loop (cost=82.84..114805.38 rows=20155 width=4) -> Bitmap Heap Scan on part (cost=73.07..6668.16 rows=2014 width=4) Recheck Cond: ((p_container = 'JUMBO BOX'::bpchar) AND (p_brand = 'Brand#51'::bpchar)) -> Bitmap Index Scan on part_p_container_p_brand_p_partkey_idx (cost=0.00..72.57 rows=2014 width=0) Index Cond: ((p_container = 'JUMBO BOX'::bpchar) AND (p_brand = 'Brand#51'::bpchar)) -> Index Scan using lineitem_l_partkey_l_quantity_idx on lineitem (cost=9.76..53.59 rows=10 width=12) Index Cond: ((l_partkey = part.p_partkey) AND (l_quantity < (SubPlan 1))) SubPlan 1 -> Aggregate (cost=9.19..9.20 rows=1 width=4) -> Index Only Scan using lineitem_l_partkey_l_quantity_idx on lineitem lineitem_1 (cost=0.56..9.11 rows=31 width=4) Index Cond: (l_partkey = part.p_partkey) Planning time: 1.947 ms (13 rows) COMMIT; COMMIT