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 '1993-01-01' and o_orderdate < date '1993-01-01' + interval '1 year' group by n_name order by revenue desc; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2436935.37..2436935.44 rows=25 width=34) (actual time=105067.094..105067.094 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=1023507 read=458950 dirtied=41 written=41 -> HashAggregate (cost=2436934.54..2436934.79 rows=25 width=34) (actual time=105066.999..105067.019 rows=5 loops=1) Buffers: shared hit=1023504 read=458950 dirtied=41 written=41 -> Hash Join (cost=401496.49..2436200.83 rows=73371 width=34) (actual time=15646.040..104827.206 rows=72082 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=1023504 read=458950 dirtied=41 written=41 -> Hash Join (cost=396817.49..2394091.72 rows=1834820 width=46) (actual time=15491.875..100344.084 rows=1817644 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=1021322 read=458950 dirtied=41 written=41 -> Seq Scan on lineitem (cost=0.00..1676902.68 rows=60404668 width=16) (actual time=0.040..39072.885 rows=60045310 loops=1) Buffers: shared hit=621181 read=451675 dirtied=41 written=41 -> Hash (cost=391082.24..391082.24 rows=458820 width=38) (actual time=15491.282..15491.282 rows=453960 loops=1) Buckets: 65536 Batches: 1 Memory Usage: 31920kB Buffers: shared hit=400141 read=7275 -> Hash Join (cost=88438.69..391082.24 rows=458820 width=38) (actual time=3299.168..15117.779 rows=453960 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=400141 read=7275 -> Bitmap Heap Scan on orders (cost=49396.47..338848.95 rows=2294099 width=8) (actual time=1768.360..6887.169 rows=2279082 loops=1) Recheck Cond: ((o_orderdate >= '1993-01-01'::date) AND (o_orderdate < '1994-01-01 00:00:00'::timestamp without time zone)) Buffers: shared hit=255029 read=6448 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..48822.94 rows=2294099 width=0) (actual time=1648.158..1648.158 rows=2292541 loops=1) Index Cond: ((o_orderdate >= '1993-01-01'::date) AND (o_orderdate < '1994-01-01 00:00:00'::timestamp without time zone)) Buffers: shared read=6448 -> Hash (cost=35292.22..35292.22 rows=300000 width=38) (actual time=1530.278..1530.278 rows=299436 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 21055kB Buffers: shared hit=145112 read=827 -> Nested Loop (cost=905.09..35292.22 rows=300000 width=38) (actual time=51.834..1309.218 rows=299436 loops=1) Buffers: shared hit=145112 read=827 -> Nested Loop (cost=0.00..14.07 rows=5 width=30) (actual time=0.067..0.167 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=0.020..0.065 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=0.027..0.028 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=40.201..238.750 rows=59887 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=145109 read=827 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=27.993..27.993 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=153.743..153.743 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=0.011..108.176 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 105079.362 ms (55 rows) COMMIT; COMMIT