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 '1995-01-01' and o_orderdate < date '1995-01-01' + interval '1 year' group by n_name order by revenue desc; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2425097.87..2425097.93 rows=25 width=34) (actual time=94359.850..94359.851 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=388475 read=1087171 dirtied=253 written=363 -> HashAggregate (cost=2425097.04..2425097.29 rows=25 width=34) (actual time=94359.758..94359.762 rows=5 loops=1) Buffers: shared hit=388472 read=1087171 dirtied=253 written=363 -> Hash Join (cost=399455.82..2424363.15 rows=73389 width=34) (actual time=22293.722..94172.501 rows=72829 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=388472 read=1087171 dirtied=253 written=363 -> Hash Join (cost=394776.82..2382256.44 rows=1834691 width=46) (actual time=22180.258..89506.176 rows=1818255 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=386290 read=1087171 dirtied=253 written=363 -> Seq Scan on lineitem (cost=0.00..1668603.81 rows=60105781 width=16) (actual time=0.041..22364.446 rows=60045603 loops=1) Buffers: shared hit=256540 read=811006 -> Hash (cost=389042.07..389042.07 rows=458780 width=38) (actual time=22179.518..22179.518 rows=454944 loops=1) Buckets: 65536 Batches: 1 Memory Usage: 31989kB Buffers: shared hit=129750 read=276165 dirtied=253 written=363 -> Hash Join (cost=87668.61..389042.07 rows=458780 width=38) (actual time=6632.814..20136.461 rows=454944 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=129750 read=276165 dirtied=253 written=363 -> Bitmap Heap Scan on orders (cost=48626.39..336809.92 rows=2293902 width=8) (actual time=3979.963..10310.373 rows=2277888 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate < '1996-01-01 00:00:00'::timestamp without time zone)) Buffers: shared hit=12286 read=247690 dirtied=253 written=363 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..48052.92 rows=2293902 width=0) (actual time=3830.418..3830.418 rows=2280135 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate < '1996-01-01 00:00:00'::timestamp without time zone)) Buffers: shared hit=324 read=5897 -> Hash (cost=35292.22..35292.22 rows=300000 width=38) (actual time=2652.392..2652.392 rows=299436 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 21055kB Buffers: shared hit=117464 read=28475 -> Nested Loop (cost=905.09..35292.22 rows=300000 width=38) (actual time=44.524..1862.220 rows=299436 loops=1) Buffers: shared hit=117464 read=28475 -> Nested Loop (cost=0.00..14.07 rows=5 width=30) (actual time=0.067..0.363 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=0.00..12.63 rows=25 width=34) (actual time=0.016..0.250 rows=25 loops=1) Buffers: shared hit=2 -> Materialize (cost=0.00..1.07 rows=1 width=4) (actual time=0.002..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=0.025..0.026 rows=1 loops=1) Filter: (r_name = 'AMERICA'::bpchar) Rows Removed by Filter: 4 Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=39.759..349.632 rows=59887 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=117461 read=28475 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=28.958..28.958 rows=59887 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=7 read=827 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=111.420..111.420 rows=100000 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 3907kB Buffers: shared hit=2179 -> Seq Scan on supplier (cost=0.00..3179.00 rows=100000 width=8) (actual time=0.014..62.780 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 94393.187 ms (55 rows) COMMIT; COMMIT