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 = 'JUMBO BAG' and l_quantity < ( select 0.2 * avg(l_quantity) from lineitem where l_partkey = p_partkey ); QUERY PLAN -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Aggregate (cost=347561.18..347561.19 rows=1 width=4) (actual time=679.071..679.071 rows=1 loops=1) Buffers: shared hit=56301 read=26261 dirtied=92 written=1421 -> Nested Loop (cost=130.19..347512.10 rows=19633 width=4) (actual time=0.733..678.162 rows=5249 loops=1) Buffers: shared hit=56301 read=26261 dirtied=92 written=1421 -> Index Only Scan using part_p_container_p_brand_p_partkey_idx on part (cost=0.43..7724.80 rows=1956 width=4) (actual time=0.132..32.273 rows=1976 loops=1) Index Cond: ((p_container = 'JUMBO BAG'::bpchar) AND (p_brand = 'Brand#51'::bpchar)) Heap Fetches: 1976 Buffers: shared read=1948 written=102 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=129.76..173.62 rows=10 width=12) (actual time=0.005..0.006 rows=3 loops=1976) Index Cond: ((l_partkey = part.p_partkey) AND (l_quantity < (SubPlan 1))) Buffers: shared hit=13199 SubPlan 1 -> Aggregate (cost=129.19..129.20 rows=1 width=4) (actual time=0.317..0.317 rows=1 loops=1976) Buffers: shared hit=43102 read=24313 dirtied=92 written=1319 -> 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=0.034..0.309 rows=30 loops=1976) Index Cond: (l_partkey = part.p_partkey) Heap Fetches: 59234 Buffers: shared hit=43102 read=24313 dirtied=92 written=1319 SubPlan 1 -> Aggregate (cost=129.19..129.20 rows=1 width=4) (actual time=0.317..0.317 rows=1 loops=1976) Buffers: shared hit=43102 read=24313 dirtied=92 written=1319 -> 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=0.034..0.309 rows=30 loops=1976) Index Cond: (l_partkey = part.p_partkey) Heap Fetches: 59234 Buffers: shared hit=43102 read=24313 dirtied=92 written=1319 Planning time: 3.043 ms Execution time: 679.242 ms (27 rows) COMMIT; COMMIT