BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select n_name, sum(l_extendedprice * (1 - l_discount)) as revenue from customer, orders, lineitem, supplier, nation, region where c_custkey = o_custkey and l_orderkey = o_orderkey and l_suppkey = s_suppkey and c_nationkey = s_nationkey and s_nationkey = n_nationkey and n_regionkey = r_regionkey and r_name = 'AMERICA' and o_orderdate >= date '1996-01-01' and o_orderdate < date '1996-01-01' + interval '1 year' group by n_name order by revenue desc; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1870128.97..1870129.03 rows=25 width=34) (actual time=14181.937..14181.938 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=2393788 read=328353 dirtied=138 written=6403 -> HashAggregate (cost=1870128.14..1870128.39 rows=25 width=34) (actual time=14181.857..14181.859 rows=5 loops=1) Group Key: nation.n_name Buffers: shared hit=2393785 read=328353 dirtied=138 written=6403 -> Hash Join (cost=93416.04..1869395.72 rows=73242 width=34) (actual time=2010.500..14098.854 rows=73258 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=2393785 read=328353 dirtied=138 written=6403 -> Nested Loop (cost=88737.04..1850251.68 rows=1831015 width=46) (actual time=1944.384..13038.157 rows=1822742 loops=1) Buffers: shared hit=2391603 read=328353 dirtied=138 written=6403 -> Hash Join (cost=88736.47..391788.55 rows=457871 width=38) (actual time=1944.321..6053.197 rows=455908 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=296061 read=111990 dirtied=138 written=1651 -> Bitmap Heap Scan on orders (cost=49694.30..339582.60 rows=2289353 width=8) (actual time=834.287..3481.633 rows=2281767 loops=1) Recheck Cond: ((o_orderdate >= '1996-01-01'::date) AND (o_orderdate < '1997-01-01 00:00:00'::timestamp without time zone)) Heap Blocks: exact=255531 Buffers: shared hit=186224 read=75889 dirtied=138 written=1607 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..49121.96 rows=2289353 width=0) (actual time=747.144..747.144 rows=2302185 loops=1) Index Cond: ((o_orderdate >= '1996-01-01'::date) AND (o_orderdate < '1997-01-01 00:00:00'::timestamp without time zone)) Buffers: shared read=6582 written=12 -> Hash (cost=35292.17..35292.17 rows=300000 width=38) (actual time=1106.533..1106.533 rows=299436 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 25151kB Buffers: shared hit=109837 read=36101 written=44 -> Nested Loop (cost=905.25..35292.17 rows=300000 width=38) (actual time=21.092..993.655 rows=299436 loops=1) Buffers: shared hit=109837 read=36101 written=44 -> Nested Loop (cost=0.14..13.95 rows=5 width=30) (actual time=0.052..0.113 rows=5 loops=1) Join Filter: (nation.n_regionkey = region.r_regionkey) Rows Removed by Join Filter: 20 Buffers: shared hit=3 -> Index Scan using pk_nation on nation (cost=0.14..12.51 rows=25 width=34) (actual time=0.011..0.033 rows=25 loops=1) Buffers: shared hit=2 -> Materialize (cost=0.00..1.07 rows=1 width=4) (actual time=0.001..0.002 rows=1 loops=25) Buffers: shared hit=1 -> Seq Scan on region (cost=0.00..1.06 rows=1 width=4) (actual time=0.016..0.017 rows=1 loops=1) Filter: (r_name = 'AMERICA'::bpchar) Rows Removed by Filter: 4 Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.11..6455.64 rows=60000 width=8) (actual time=18.148..185.649 rows=59887 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Heap Blocks: exact=145102 Buffers: shared hit=109834 read=36101 written=44 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=11.790..11.790 rows=59887 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=7 read=826 written=1 -> Index Scan using pk_lineitem on lineitem (cost=0.56..3.04 rows=15 width=16) (actual time=0.012..0.014 rows=4 loops=455908) Index Cond: (l_orderkey = orders.o_orderkey) Buffers: shared hit=2095542 read=216363 written=4752 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=64.882..64.882 rows=100000 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 4931kB Buffers: shared hit=2179 -> Seq Scan on supplier (cost=0.00..3179.00 rows=100000 width=8) (actual time=0.011..37.813 rows=100000 loops=1) Buffers: shared hit=2179 Planning time: 7.451 ms Execution time: 14184.125 ms (56 rows) COMMIT; COMMIT