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 '1994-01-01' and o_orderdate < date '1994-01-01' + interval '1 year' group by n_name order by revenue desc; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2447304.94..2447305.01 rows=25 width=34) (actual time=65084.463..65084.464 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=649629 read=838465 written=135 -> HashAggregate (cost=2447304.11..2447304.36 rows=25 width=34) (actual time=65084.357..65084.359 rows=5 loops=1) Buffers: shared hit=649626 read=838465 written=135 -> Hash Join (cost=403617.60..2446566.10 rows=73801 width=34) (actual time=11507.097..64982.025 rows=73230 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=649626 read=838465 written=135 -> Hash Join (cost=398938.60..2404207.79 rows=1847065 width=46) (actual time=11389.821..61385.491 rows=1828477 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=647444 read=838465 written=135 -> Seq Scan on lineitem (cost=0.00..1683572.36 rows=60645236 width=16) (actual time=0.038..13507.618 rows=59984826 loops=1) Buffers: shared hit=331250 read=745870 -> Hash (cost=393165.14..393165.14 rows=461877 width=38) (actual time=11389.376..11389.376 rows=456889 loops=1) Buckets: 65536 Batches: 1 Memory Usage: 32126kB Buffers: shared hit=316194 read=92595 written=135 -> Hash Join (cost=89191.40..393165.14 rows=461877 width=38) (actual time=2613.648..11126.360 rows=456889 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=316194 read=92595 written=135 -> Bitmap Heap Scan on orders (cost=50149.18..340843.96 rows=2309385 width=8) (actual time=1377.860..4362.879 rows=2275749 loops=1) Recheck Cond: ((o_orderdate >= '1994-01-01'::date) AND (o_orderdate < '1995-01-01 00:00:00'::timestamp without time zone)) Buffers: shared hit=206123 read=56488 written=35 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..49571.84 rows=2309385 width=0) (actual time=1264.588..1264.588 rows=2301000 loops=1) Index Cond: ((o_orderdate >= '1994-01-01'::date) AND (o_orderdate < '1995-01-01 00:00:00'::timestamp without time zone)) Buffers: shared read=6579 written=14 -> Hash (cost=35292.22..35292.22 rows=300000 width=38) (actual time=1235.054..1235.054 rows=300963 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 21162kB Buffers: shared hit=110071 read=36107 written=100 -> Nested Loop (cost=905.09..35292.22 rows=300000 width=38) (actual time=21.519..1094.678 rows=300963 loops=1) Buffers: shared hit=110071 read=36107 written=100 -> Nested Loop (cost=0.00..14.07 rows=5 width=30) (actual time=0.059..0.125 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=0.012..0.037 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=0.026..0.027 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=22.432..203.731 rows=60193 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=110068 read=36107 written=100 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=14.825..14.825 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=115.958..115.958 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=0.014..73.502 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 65097.924 ms (55 rows) COMMIT; COMMIT