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 = 'EUROPE' 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=2448600.09..2448600.15 rows=25 width=34) (actual time=112691.673..112691.673 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=860061 read=629382 dirtied=253 written=1061 -> HashAggregate (cost=2448599.26..2448599.51 rows=25 width=34) (actual time=112691.566..112691.570 rows=5 loops=1) Buffers: shared hit=860058 read=629382 dirtied=253 written=1061 -> Hash Join (cost=403275.26..2447864.89 rows=73437 width=34) (actual time=19540.034..112429.754 rows=73121 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=860058 read=629382 dirtied=253 written=1061 -> Hash Join (cost=398596.26..2405722.08 rows=1836472 width=46) (actual time=19373.283..107758.272 rows=1830604 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=857876 read=629382 dirtied=253 written=1061 -> Seq Scan on lineitem (cost=0.00..1685236.74 rows=60704874 width=16) (actual time=0.079..40300.314 rows=60044994 loops=1) Buffers: shared hit=456245 read=621943 written=1 -> Hash (cost=392855.89..392855.89 rows=459230 width=38) (actual time=19372.466..19372.466 rows=457907 loops=1) Buckets: 65536 Batches: 1 Memory Usage: 32197kB Buffers: shared hit=401631 read=7439 dirtied=253 written=1060 -> Hash Join (cost=88903.76..392855.89 rows=459230 width=38) (actual time=5409.750..18970.647 rows=457907 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=401631 read=7439 dirtied=253 written=1060 -> Bitmap Heap Scan on orders (cost=49861.54..340610.80 rows=2296151 width=8) (actual time=2291.147..9120.664 rows=2284263 loops=1) Recheck Cond: ((o_orderdate >= '1996-01-01'::date) AND (o_orderdate < '1997-01-01 00:00:00'::timestamp without time zone)) Buffers: shared hit=256425 read=6467 dirtied=253 written=918 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..49287.50 rows=2296151 width=0) (actual time=2132.768..2132.768 rows=2309258 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 hit=388 read=6214 written=918 -> Hash (cost=35292.22..35292.22 rows=300000 width=38) (actual time=3118.340..3118.340 rows=300963 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 21162kB Buffers: shared hit=145206 read=972 written=142 -> Nested Loop (cost=905.09..35292.22 rows=300000 width=38) (actual time=51.850..2882.220 rows=300963 loops=1) Buffers: shared hit=145206 read=972 written=142 -> Nested Loop (cost=0.00..14.07 rows=5 width=30) (actual time=0.052..0.173 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=0.010..0.063 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=0.020..0.020 rows=1 loops=1) Filter: (r_name = 'EUROPE'::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=42.962..551.073 rows=60193 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=145203 read=972 written=142 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=33.573..33.573 rows=60193 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=10 read=829 written=123 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=165.438..165.438 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=0.016..117.981 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 112706.660 ms (55 rows) COMMIT; COMMIT