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 '1997-01-01' and o_orderdate < date '1997-01-01' + interval '1 year' group by n_name order by revenue desc; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1867514.04..1867514.10 rows=25 width=34) (actual time=13845.849..13845.849 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=2343906 read=374687 dirtied=78 written=922 -> HashAggregate (cost=1867513.21..1867513.46 rows=25 width=34) (actual time=13845.792..13845.795 rows=5 loops=1) Group Key: nation.n_name Buffers: shared hit=2343903 read=374687 dirtied=78 written=922 -> Hash Join (cost=92737.25..1866777.90 rows=73531 width=34) (actual time=2462.991..13771.617 rows=72777 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=2343903 read=374687 dirtied=78 written=922 -> Nested Loop (cost=88058.25..1847576.13 rows=1838328 width=46) (actual time=2390.310..13072.141 rows=1821459 loops=1) Buffers: shared hit=2341721 read=374687 dirtied=78 written=922 -> Hash Join (cost=88057.69..390537.46 rows=459689 width=38) (actual time=2390.275..5965.070 rows=455374 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=356185 read=50853 dirtied=78 written=419 -> Bitmap Heap Scan on orders (cost=49015.52..338279.22 rows=2298447 width=8) (actual time=1292.717..3370.969 rows=2278036 loops=1) Recheck Cond: ((o_orderdate >= '1997-01-01'::date) AND (o_orderdate < '1998-01-01 00:00:00'::timestamp without time zone)) Heap Blocks: exact=254769 Buffers: shared hit=246347 read=14753 dirtied=78 written=128 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..48440.90 rows=2298447 width=0) (actual time=1176.350..1176.350 rows=2289343 loops=1) Index Cond: ((o_orderdate >= '1997-01-01'::date) AND (o_orderdate < '1998-01-01 00:00:00'::timestamp without time zone)) Buffers: shared hit=305 read=6026 written=48 -> Hash (cost=35292.17..35292.17 rows=300000 width=38) (actual time=1093.308..1093.308 rows=299436 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 25151kB Buffers: shared hit=109838 read=36100 written=291 -> Nested Loop (cost=905.25..35292.17 rows=300000 width=38) (actual time=18.649..961.938 rows=299436 loops=1) Buffers: shared hit=109838 read=36100 written=291 -> Nested Loop (cost=0.14..13.95 rows=5 width=30) (actual time=0.045..0.105 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=0.013..0.040 rows=25 loops=1) Buffers: shared hit=2 -> Materialize (cost=0.00..1.07 rows=1 width=4) (actual time=0.001..0.001 rows=1 loops=25) Buffers: shared hit=1 -> Seq Scan on region (cost=0.00..1.06 rows=1 width=4) (actual time=0.013..0.014 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=17.291..179.491 rows=59887 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Heap Blocks: exact=145102 Buffers: shared hit=109835 read=36100 written=291 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=11.377..11.377 rows=59887 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=7 read=826 written=8 -> Index Scan using lineitem_l_orderkey_idx on lineitem (cost=0.56..3.02 rows=15 width=16) (actual time=0.012..0.014 rows=4 loops=455374) Index Cond: (l_orderkey = orders.o_orderkey) Buffers: shared hit=1985536 read=323834 written=503 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=71.821..71.821 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=0.010..47.695 rows=100000 loops=1) Buffers: shared hit=2179 Planning time: 6.751 ms Execution time: 13847.822 ms (56 rows) COMMIT; COMMIT