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#31' and p_container = 'SM CAN' and l_quantity < ( select 0.2 * avg(l_quantity) from lineitem where l_partkey = p_partkey ); QUERY PLAN --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Aggregate (cost=398682.09..398682.10 rows=1 width=4) (actual time=1596.308..1596.308 rows=1 loops=1) Buffers: shared hit=54722 read=30565 dirtied=61 -> Nested Loop (cost=140.78..398632.33 rows=19905 width=4) (actual time=0.919..1594.558 rows=5473 loops=1) Buffers: shared hit=54722 read=30565 dirtied=61 -> Index Only Scan using part_p_container_p_brand_p_partkey_idx on part (cost=0.00..7841.95 rows=1985 width=4) (actual time=0.281..68.341 rows=2026 loops=1) Index Cond: ((p_container = 'SM CAN'::bpchar) AND (p_brand = 'Brand#31'::bpchar)) Heap Fetches: 2026 Buffers: shared read=1982 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=140.78..196.77 rows=10 width=12) (actual time=0.023..0.035 rows=3 loops=2026) Index Cond: ((l_partkey = part.p_partkey) AND (l_quantity < (SubPlan 1))) Buffers: shared hit=13623 SubPlan 1 -> Aggregate (cost=140.77..140.78 rows=1 width=4) (actual time=0.712..0.712 rows=1 loops=2026) Buffers: shared hit=41099 read=28583 dirtied=61 -> Index Only Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..140.69 rows=31 width=4) (actual time=0.071..0.697 rows=30 loops=2026) Index Cond: (l_partkey = part.p_partkey) Heap Fetches: 61273 Buffers: shared hit=41099 read=28583 dirtied=61 SubPlan 1 -> Aggregate (cost=140.77..140.78 rows=1 width=4) (actual time=0.712..0.712 rows=1 loops=2026) Buffers: shared hit=41099 read=28583 dirtied=61 -> Index Only Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..140.69 rows=31 width=4) (actual time=0.071..0.697 rows=30 loops=2026) Index Cond: (l_partkey = part.p_partkey) Heap Fetches: 61273 Buffers: shared hit=41099 read=28583 dirtied=61 Total runtime: 1596.517 ms (26 rows) COMMIT; COMMIT