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 = 'ASIA' 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=2422736.08..2422736.14 rows=25 width=34) (actual time=86299.923..86299.924 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=1034496 read=440126 written=1918 -> HashAggregate (cost=2422735.25..2422735.50 rows=25 width=34) (actual time=86299.855..86299.857 rows=5 loops=1) Buffers: shared hit=1034493 read=440126 written=1918 -> Hash Join (cost=399126.22..2422002.10 rows=73315 width=34) (actual time=16219.301..86115.790 rows=73146 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=1034493 read=440126 written=1918 -> Hash Join (cost=394447.22..2379932.93 rows=1832851 width=46) (actual time=16125.684..82168.136 rows=1825440 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=1034476 read=437961 written=1918 -> Seq Scan on lineitem (cost=0.00..1666929.80 rows=60045480 width=16) (actual time=0.010..20973.809 rows=59985329 loops=1) Buffers: shared hit=690796 read=375679 written=3 -> Hash (cost=388718.18..388718.18 rows=458323 width=38) (actual time=16125.261..16125.261 rows=455986 loops=1) Buckets: 65536 Batches: 1 Memory Usage: 32062kB Buffers: shared hit=343680 read=62282 written=1915 -> Hash Join (cost=87645.17..388718.18 rows=458323 width=38) (actual time=4656.734..15508.873 rows=455986 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=343680 read=62282 written=1915 -> Bitmap Heap Scan on orders (cost=48602.95..336499.17 rows=2291615 width=8) (actual time=2385.544..6683.713 rows=2275583 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=213703 read=46020 written=1915 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..48030.05 rows=2291615 width=0) (actual time=2237.589..2237.589 rows=2277830 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=6221 -> Hash (cost=35292.22..35292.22 rows=300000 width=38) (actual time=2271.000..2271.000 rows=300270 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 21113kB Buffers: shared hit=129977 read=16262 -> Nested Loop (cost=905.09..35292.22 rows=300000 width=38) (actual time=34.563..1817.926 rows=300270 loops=1) Buffers: shared hit=129977 read=16262 -> Nested Loop (cost=0.00..14.07 rows=5 width=30) (actual time=0.061..0.172 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=0.012..0.058 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=0.026..0.027 rows=1 loops=1) Filter: (r_name = 'ASIA'::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=35.505..337.918 rows=60054 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=129974 read=16262 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=24.649..24.649 rows=60054 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=5 read=831 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=93.189..93.189 rows=100000 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 3907kB Buffers: shared hit=14 read=2165 -> Seq Scan on supplier (cost=0.00..3179.00 rows=100000 width=8) (actual time=0.010..55.768 rows=100000 loops=1) Buffers: shared hit=14 read=2165 Total runtime: 86327.768 ms (55 rows) COMMIT; COMMIT