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 '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=1863365.06..1863365.13 rows=25 width=34) (actual time=12534.039..12534.040 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=2154231 read=575246 dirtied=354 written=3901 -> HashAggregate (cost=1863364.23..1863364.48 rows=25 width=34) (actual time=12533.958..12533.960 rows=5 loops=1) Group Key: nation.n_name Buffers: shared hit=2154228 read=575246 dirtied=354 written=3901 -> Hash Join (cost=92226.74..1862632.69 rows=73154 width=34) (actual time=1712.078..12454.501 rows=72833 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=2154228 read=575246 dirtied=354 written=3901 -> Nested Loop (cost=87547.74..1843494.73 rows=1830323 width=46) (actual time=1655.300..11785.152 rows=1829460 loops=1) Buffers: shared hit=2152046 read=575246 dirtied=354 written=3901 -> Hash Join (cost=87547.18..389566.43 rows=457689 width=38) (actual time=1655.223..5050.509 rows=457506 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=232563 read=174380 dirtied=354 written=2003 -> Bitmap Heap Scan on orders (cost=48505.01..337365.70 rows=2288446 width=8) (actual time=757.878..3271.367 rows=2279107 loops=1) Recheck Cond: ((o_orderdate >= '1993-01-01'::date) AND (o_orderdate < '1994-01-01 00:00:00'::timestamp without time zone)) Heap Blocks: exact=254522 Buffers: shared hit=122477 read=138289 dirtied=354 written=778 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..47932.89 rows=2288446 width=0) (actual time=677.217..677.217 rows=2288014 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=372 read=5872 written=90 -> Hash (cost=35292.17..35292.17 rows=300000 width=38) (actual time=894.669..894.669 rows=300963 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 25258kB Buffers: shared hit=110086 read=36091 written=1225 -> Nested Loop (cost=905.25..35292.17 rows=300000 width=38) (actual time=18.153..790.576 rows=300963 loops=1) Buffers: shared hit=110086 read=36091 written=1225 -> Nested Loop (cost=0.14..13.95 rows=5 width=30) (actual time=0.042..0.095 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=0.14..12.51 rows=25 width=34) (actual time=0.007..0.026 rows=25 loops=1) Buffers: shared hit=2 -> Materialize (cost=0.00..1.07 rows=1 width=4) (actual time=0.001..0.001 rows=1 loops=25) Buffers: shared hit=1 -> Seq Scan on region (cost=0.00..1.06 rows=1 width=4) (actual time=0.014..0.014 rows=1 loops=1) Filter: (r_name = 'EUROPE'::bpchar) Rows Removed by Filter: 4 Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.11..6455.64 rows=60000 width=8) (actual time=16.522..146.035 rows=60193 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Heap Blocks: exact=145336 Buffers: shared hit=110083 read=36091 written=1225 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=10.804..10.804 rows=60193 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=6 read=832 written=16 -> Index Scan using lineitem_l_orderkey_idx on lineitem (cost=0.56..3.03 rows=15 width=16) (actual time=0.012..0.013 rows=4 loops=457506) Index Cond: (l_orderkey = orders.o_orderkey) Buffers: shared hit=1919483 read=400866 written=1898 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=55.959..55.959 rows=100000 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 4931kB Buffers: shared hit=2179 -> Seq Scan on supplier (cost=0.00..3179.00 rows=100000 width=8) (actual time=0.008..32.408 rows=100000 loops=1) Buffers: shared hit=2179 Planning time: 5.851 ms Execution time: 12536.891 ms (56 rows) COMMIT; COMMIT