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#55' and p_container = 'SM PKG' and l_quantity < ( select 0.2 * avg(l_quantity) from lineitem where l_partkey = p_partkey ); QUERY PLAN -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Aggregate (cost=353593.94..353593.95 rows=1 width=4) (actual time=776.318..776.318 rows=1 loops=1) Buffers: shared hit=51880 read=32130 dirtied=62 written=35 -> Nested Loop (cost=130.19..353544.05 rows=19955 width=4) (actual time=0.881..775.416 rows=5342 loops=1) Buffers: shared hit=51880 read=32130 dirtied=62 written=35 -> Index Only Scan using part_p_container_p_brand_p_partkey_idx on part (cost=0.43..7860.97 rows=1990 width=4) (actual time=0.136..34.679 rows=1994 loops=1) Index Cond: ((p_container = 'SM PKG'::bpchar) AND (p_brand = 'Brand#55'::bpchar)) Heap Fetches: 1994 Buffers: shared read=1966 written=2 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=129.76..173.61 rows=10 width=12) (actual time=0.006..0.007 rows=3 loops=1994) Index Cond: ((l_partkey = part.p_partkey) AND (l_quantity < (SubPlan 1))) Buffers: shared hit=13360 SubPlan 1 -> Aggregate (cost=129.19..129.20 rows=1 width=4) (actual time=0.361..0.361 rows=1 loops=1994) Buffers: shared hit=38520 read=30164 dirtied=62 written=33 -> 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..0.352 rows=30 loops=1994) Index Cond: (l_partkey = part.p_partkey) Heap Fetches: 60393 Buffers: shared hit=38520 read=30164 dirtied=62 written=33 SubPlan 1 -> Aggregate (cost=129.19..129.20 rows=1 width=4) (actual time=0.361..0.361 rows=1 loops=1994) Buffers: shared hit=38520 read=30164 dirtied=62 written=33 -> 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..0.352 rows=30 loops=1994) Index Cond: (l_partkey = part.p_partkey) Heap Fetches: 60393 Buffers: shared hit=38520 read=30164 dirtied=62 written=33 Planning time: 3.774 ms Execution time: 776.520 ms (27 rows) COMMIT; COMMIT