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 = 'JUMBO DRUM' and l_quantity < ( select 0.2 * avg(l_quantity) from lineitem where l_partkey = p_partkey ); QUERY PLAN -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Aggregate (cost=357319.68..357319.69 rows=1 width=4) (actual time=813.632..813.632 rows=1 loops=1) Buffers: shared hit=54971 read=31330 dirtied=319 written=170 -> Nested Loop (cost=130.19..357268.96 rows=20286 width=4) (actual time=0.721..812.592 rows=5476 loops=1) Buffers: shared hit=54971 read=31330 dirtied=319 written=170 -> Index Only Scan using part_p_container_p_brand_p_partkey_idx on part (cost=0.43..7942.14 rows=2011 width=4) (actual time=0.142..34.688 rows=2050 loops=1) Index Cond: ((p_container = 'JUMBO DRUM'::bpchar) AND (p_brand = 'Brand#31'::bpchar)) Heap Fetches: 2050 Buffers: shared hit=281 read=1729 written=9 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=129.76..173.61 rows=10 width=12) (actual time=0.005..0.007 rows=3 loops=2050) Index Cond: ((l_partkey = part.p_partkey) AND (l_quantity < (SubPlan 1))) Buffers: shared hit=13724 SubPlan 1 -> Aggregate (cost=129.19..129.20 rows=1 width=4) (actual time=0.369..0.369 rows=1 loops=2050) Buffers: shared hit=40966 read=29601 dirtied=319 written=161 -> 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=0.038..0.360 rows=30 loops=2050) Index Cond: (l_partkey = part.p_partkey) Heap Fetches: 62044 Buffers: shared hit=40966 read=29601 dirtied=319 written=161 SubPlan 1 -> Aggregate (cost=129.19..129.20 rows=1 width=4) (actual time=0.369..0.369 rows=1 loops=2050) Buffers: shared hit=40966 read=29601 dirtied=319 written=161 -> 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=0.038..0.360 rows=30 loops=2050) Index Cond: (l_partkey = part.p_partkey) Heap Fetches: 62044 Buffers: shared hit=40966 read=29601 dirtied=319 written=161 Planning time: 3.687 ms Execution time: 813.830 ms (27 rows) COMMIT; COMMIT