BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) 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 = 'MED CASE' and l_quantity < ( select 0.2 * avg(l_quantity) from lineitem where l_partkey = p_partkey ); QUERY PLAN -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Aggregate (cost=358200.87..358200.88 rows=1 width=4) (actual time=799.155..799.155 rows=1 loops=1) Buffers: shared hit=49047 read=35213 dirtied=61 -> Nested Loop (cost=130.19..358150.38 rows=20196 width=4) (actual time=0.837..798.104 rows=5487 loops=1) Buffers: shared hit=49047 read=35213 dirtied=61 -> Index Only Scan using part_p_container_p_brand_p_partkey_idx on part (cost=0.43..7961.34 rows=2016 width=4) (actual time=0.155..33.687 rows=2009 loops=1) Index Cond: ((p_container = 'MED CASE'::bpchar) AND (p_brand = 'Brand#51'::bpchar)) Heap Fetches: 2009 Buffers: shared read=1981 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=129.76..173.60 rows=10 width=12) (actual time=0.006..0.007 rows=3 loops=2009) Index Cond: ((l_partkey = part.p_partkey) AND (l_quantity < (SubPlan 1))) Buffers: shared hit=13562 SubPlan 1 -> Aggregate (cost=129.19..129.20 rows=1 width=4) (actual time=0.370..0.370 rows=1 loops=2009) Buffers: shared hit=35485 read=33232 dirtied=61 -> Index Only Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem lineitem_1 (cost=0.56..129.11 rows=31 width=4) (actual time=0.039..0.360 rows=30 loops=2009) Index Cond: (l_partkey = part.p_partkey) Heap Fetches: 60391 Buffers: shared hit=35485 read=33232 dirtied=61 SubPlan 1 -> Aggregate (cost=129.19..129.20 rows=1 width=4) (actual time=0.370..0.370 rows=1 loops=2009) Buffers: shared hit=35485 read=33232 dirtied=61 -> Index Only Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem lineitem_1 (cost=0.56..129.11 rows=31 width=4) (actual time=0.039..0.360 rows=30 loops=2009) Index Cond: (l_partkey = part.p_partkey) Heap Fetches: 60391 Buffers: shared hit=35485 read=33232 dirtied=61 Planning time: 3.379 ms Execution time: 799.340 ms (27 rows) COMMIT; COMMIT