BEGIN; BEGIN EXPLAIN select sum(l_extendedprice) / 7.0 as avg_yearly from lineitem, part where p_partkey = l_partkey and p_brand = 'Brand#45' and p_container = 'SM DRUM' and l_quantity < ( select 0.2 * avg(l_quantity) from lineitem where l_partkey = p_partkey ); QUERY PLAN -------------------------------------------------------------------------------------------------------------------------------------------------------- Aggregate (cost=111362.89..111362.90 rows=1 width=32) -> Nested Loop (cost=10.17..111311.05 rows=20735 width=8) -> Index Only Scan using part_p_container_p_brand_p_partkey_idx on part (cost=0.43..89.87 rows=2072 width=4) Index Cond: ((p_container = 'SM DRUM'::bpchar) AND (p_brand = 'Brand#45'::bpchar)) -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=9.74..53.58 rows=10 width=17) Index Cond: ((l_partkey = part.p_partkey) AND (l_quantity < (SubPlan 1))) SubPlan 1 -> Aggregate (cost=9.17..9.18 rows=1 width=32) -> Index Only Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem lineitem_1 (cost=0.56..9.09 rows=30 width=5) Index Cond: (l_partkey = part.p_partkey) (10 rows) COMMIT; COMMIT