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=2446400.63..2446400.70 rows=25 width=34) (actual time=85204.980..85204.980 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=899270 read=588846 dirtied=253 written=17 -> HashAggregate (cost=2446399.80..2446400.05 rows=25 width=34) (actual time=85204.711..85204.712 rows=5 loops=1) Buffers: shared hit=899267 read=588846 dirtied=253 written=17 -> Hash Join (cost=403031.65..2445665.15 rows=73465 width=34) (actual time=17606.577..85021.959 rows=73112 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=899267 read=588846 dirtied=253 written=17 -> Hash Join (cost=398352.65..2403519.24 rows=1836613 width=46) (actual time=17447.956..81012.119 rows=1830368 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=897085 read=588846 dirtied=253 written=17 -> Seq Scan on lineitem (cost=0.00..1683573.65 rows=60645365 width=16) (actual time=0.049..21990.624 rows=60044872 loops=1) Buffers: shared hit=620523 read=456597 -> Hash (cost=392611.87..392611.87 rows=459262 width=38) (actual time=17447.174..17447.174 rows=457859 loops=1) Buckets: 65536 Batches: 1 Memory Usage: 32194kB Buffers: shared hit=276562 read=132249 dirtied=253 written=17 -> Hash Join (cost=88909.40..392611.87 rows=459262 width=38) (actual time=4702.918..17040.583 rows=457859 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=276562 read=132249 dirtied=253 written=17 -> Bitmap Heap Scan on orders (cost=49867.19..340365.87 rows=2296312 width=8) (actual time=2224.849..7730.961 rows=2284200 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=160592 read=102041 dirtied=253 written=17 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..49293.11 rows=2296312 width=0) (actual time=2103.728..2103.728 rows=2306946 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=6596 written=9 -> Hash (cost=35292.22..35292.22 rows=300000 width=38) (actual time=2477.743..2477.743 rows=300963 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 21162kB Buffers: shared hit=115970 read=30208 -> Nested Loop (cost=905.09..35292.22 rows=300000 width=38) (actual time=36.677..2241.343 rows=300963 loops=1) Buffers: shared hit=115970 read=30208 -> Nested Loop (cost=0.00..14.07 rows=5 width=30) (actual time=0.086..0.187 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..0.063 rows=25 loops=1) Buffers: shared hit=2 -> Materialize (cost=0.00..1.07 rows=1 width=4) (actual time=0.002..0.003 rows=1 loops=25) Buffers: shared hit=1 -> Seq Scan on region (cost=0.00..1.06 rows=1 width=4) (actual time=0.041..0.042 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=35.895..419.387 rows=60193 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=115967 read=30208 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=25.166..25.166 rows=60193 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=6 read=833 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=157.066..157.066 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..102.668 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 85213.235 ms (55 rows) COMMIT; COMMIT