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 '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=2449321.22..2449321.28 rows=25 width=34) (actual time=79600.353..79600.354 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=1385060 read=104359 dirtied=253 written=353 -> HashAggregate (cost=2449320.39..2449320.64 rows=25 width=34) (actual time=79600.272..79600.276 rows=5 loops=1) Buffers: shared hit=1385057 read=104359 dirtied=253 written=353 -> Hash Join (cost=403739.36..2448582.48 rows=73791 width=34) (actual time=14006.951..79435.349 rows=72642 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=1385057 read=104359 dirtied=253 written=353 -> Hash Join (cost=399060.36..2406269.89 rows=1844784 width=46) (actual time=13892.070..75109.225 rows=1823880 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=1382875 read=104359 dirtied=253 written=353 -> Seq Scan on lineitem (cost=0.00..1685237.14 rows=60704914 width=16) (actual time=0.037..18639.338 rows=60044994 loops=1) Buffers: shared hit=1006739 read=71449 written=3 -> Hash (cost=393294.01..393294.01 rows=461308 width=38) (actual time=13891.218..13891.218 rows=456016 loops=1) Buckets: 65536 Batches: 1 Memory Usage: 32064kB Buffers: shared hit=376136 read=32910 dirtied=253 written=350 -> Hash Join (cost=89126.26..393294.01 rows=461308 width=38) (actual time=3664.920..13564.782 rows=456016 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=376136 read=32910 dirtied=253 written=350 -> Bitmap Heap Scan on orders (cost=50084.05..340989.18 rows=2306542 width=8) (actual time=1831.432..5362.257 rows=2277498 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=252886 read=9982 dirtied=253 written=1 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..49507.41 rows=2306542 width=0) (actual time=1698.295..1698.295 rows=2302785 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=267 read=6314 -> Hash (cost=35292.22..35292.22 rows=300000 width=38) (actual time=1833.017..1833.017 rows=300963 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 21162kB Buffers: shared hit=123250 read=22928 written=349 -> Nested Loop (cost=905.09..35292.22 rows=300000 width=38) (actual time=32.942..1609.288 rows=300963 loops=1) Buffers: shared hit=123250 read=22928 written=349 -> Nested Loop (cost=0.00..14.07 rows=5 width=30) (actual time=0.067..0.286 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=0.011..0.162 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=0.028..0.028 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=34.803..297.561 rows=60193 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=123247 read=22928 written=349 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=23.515..23.515 rows=60193 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=6 read=833 written=14 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=113.726..113.726 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..71.262 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 79616.370 ms (55 rows) COMMIT; COMMIT