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=2425897.31..2425897.37 rows=25 width=34) (actual time=97738.097..97738.097 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=817711 read=659262 dirtied=253 written=107 -> HashAggregate (cost=2425896.48..2425896.73 rows=25 width=34) (actual time=97738.023..97738.027 rows=5 loops=1) Buffers: shared hit=817708 read=659262 dirtied=253 written=107 -> Hash Join (cost=398791.55..2425169.02 rows=72746 width=34) (actual time=17880.537..97464.474 rows=72110 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=817708 read=659262 dirtied=253 written=107 -> Hash Join (cost=394112.55..2383390.30 rows=1818613 width=46) (actual time=17728.577..93248.335 rows=1817304 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=815530 read=659258 dirtied=253 written=107 -> Seq Scan on lineitem (cost=0.00..1670263.74 rows=60165574 width=16) (actual time=0.068..28140.602 rows=60045379 loops=1) Buffers: shared hit=510521 read=558087 -> Hash (cost=388428.04..388428.04 rows=454761 width=38) (actual time=17727.946..17727.946 rows=453907 loops=1) Buckets: 65536 Batches: 1 Memory Usage: 31916kB Buffers: shared hit=305009 read=101171 dirtied=253 written=107 -> Hash Join (cost=87218.60..388428.04 rows=454761 width=38) (actual time=3917.219..15062.332 rows=453907 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=305009 read=101171 dirtied=253 written=107 -> Bitmap Heap Scan on orders (cost=48176.39..336311.45 rows=2273804 width=8) (actual time=1594.342..6333.731 rows=2279110 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=159728 read=100513 dirtied=253 written=107 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..47607.94 rows=2273804 width=0) (actual time=1472.185..1472.185 rows=2283473 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 hit=154 read=6071 written=57 -> Hash (cost=35292.22..35292.22 rows=300000 width=38) (actual time=2322.365..2322.365 rows=299436 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 21055kB Buffers: shared hit=145281 read=658 -> Nested Loop (cost=905.09..35292.22 rows=300000 width=38) (actual time=39.138..2089.678 rows=299436 loops=1) Buffers: shared hit=145281 read=658 -> Nested Loop (cost=0.00..14.07 rows=5 width=30) (actual time=0.057..0.183 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=0.013..0.062 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=0.025..0.027 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=36.594..389.883 rows=59887 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=145278 read=658 -> 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=59887 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=176 read=658 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=149.790..149.790 rows=100000 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 3907kB Buffers: shared hit=2175 read=4 -> Seq Scan on supplier (cost=0.00..3179.00 rows=100000 width=8) (actual time=0.009..100.272 rows=100000 loops=1) Buffers: shared hit=2175 read=4 Total runtime: 97775.863 ms (55 rows) COMMIT; COMMIT