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 '1997-01-01' and o_orderdate < date '1997-01-01' + interval '1 year' group by n_name order by revenue desc; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2444497.91..2444497.97 rows=25 width=34) (actual time=89383.541..89383.542 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=814406 read=672356 dirtied=1 written=7 -> HashAggregate (cost=2444497.08..2444497.33 rows=25 width=34) (actual time=89383.467..89383.470 rows=5 loops=1) Buffers: shared hit=814403 read=672356 dirtied=1 written=7 -> Hash Join (cost=402997.25..2443760.86 rows=73622 width=34) (actual time=13881.431..89153.706 rows=73119 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=814403 read=672356 dirtied=1 written=7 -> Hash Join (cost=398318.25..2401534.52 rows=1840556 width=46) (actual time=13772.977..84726.899 rows=1826548 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=812221 read=672356 dirtied=1 written=7 -> Seq Scan on lineitem (cost=0.00..1681889.14 rows=60584314 width=16) (actual time=0.020..23707.720 rows=60044176 loops=1) Buffers: shared hit=416717 read=659329 dirtied=1 written=1 -> Hash (cost=392565.04..392565.04 rows=460257 width=38) (actual time=13772.457..13772.457 rows=457420 loops=1) Buckets: 65536 Batches: 1 Memory Usage: 32163kB Buffers: shared hit=395504 read=13027 written=6 -> Hash Join (cost=89012.38..392565.04 rows=460257 width=38) (actual time=2735.983..12782.421 rows=457420 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=395504 read=13027 written=6 -> Bitmap Heap Scan on orders (cost=49970.16..340290.43 rows=2301285 width=8) (actual time=1341.689..4775.098 rows=2277992 loops=1) Recheck Cond: ((o_orderdate >= '1997-01-01'::date) AND (o_orderdate < '1998-01-01 00:00:00'::timestamp without time zone)) Buffers: shared hit=250336 read=12017 written=6 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..49394.84 rows=2301285 width=0) (actual time=1203.013..1203.013 rows=2298387 loops=1) Index Cond: ((o_orderdate >= '1997-01-01'::date) AND (o_orderdate < '1998-01-01 00:00:00'::timestamp without time zone)) Buffers: shared read=6570 -> Hash (cost=35292.22..35292.22 rows=300000 width=38) (actual time=1394.051..1394.051 rows=300963 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 21162kB Buffers: shared hit=145168 read=1010 -> Nested Loop (cost=905.09..35292.22 rows=300000 width=38) (actual time=29.846..1201.520 rows=300963 loops=1) Buffers: shared hit=145168 read=1010 -> Nested Loop (cost=0.00..14.07 rows=5 width=30) (actual time=0.064..0.163 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=0.015..0.050 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..0.025 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=29.725..219.131 rows=60193 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=145165 read=1010 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=19.124..19.124 rows=60193 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=10 read=829 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=107.465..107.465 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=0.008..67.672 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 89422.473 ms (55 rows) COMMIT; COMMIT