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 = 'ASIA' and o_orderdate >= date '1995-01-01' and o_orderdate < date '1995-01-01' + interval '1 year' group by n_name order by revenue desc; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1868939.02..1868939.09 rows=25 width=34) (actual time=13767.192..13767.192 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=2349004 read=376365 dirtied=30 written=810 -> HashAggregate (cost=1868938.19..1868938.44 rows=25 width=34) (actual time=13767.131..13767.131 rows=5 loops=1) Group Key: nation.n_name Buffers: shared hit=2349001 read=376365 dirtied=30 written=810 -> Hash Join (cost=93342.14..1868206.22 rows=73197 width=34) (actual time=1818.619..13688.085 rows=73272 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=2349001 read=376365 dirtied=30 written=810 -> Nested Loop (cost=88663.14..1849056.77 rows=1831798 width=46) (actual time=1754.124..12977.916 rows=1827261 loops=1) Buffers: shared hit=2346819 read=376365 dirtied=30 written=810 -> Hash Join (cost=88662.58..391482.12 rows=458068 width=38) (actual time=1754.042..5302.585 rows=456512 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=347363 read=60673 dirtied=30 written=162 -> Bitmap Heap Scan on orders (cost=49620.41..339270.49 rows=2290339 width=8) (actual time=907.867..3501.476 rows=2277660 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate < '1996-01-01 00:00:00'::timestamp without time zone)) Heap Blocks: exact=255274 Buffers: shared hit=201974 read=59824 dirtied=30 written=160 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..49047.82 rows=2290339 width=0) (actual time=816.183..816.183 rows=2293711 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate < '1996-01-01 00:00:00'::timestamp without time zone)) Buffers: shared hit=1 read=6523 written=18 -> Hash (cost=35292.17..35292.17 rows=300000 width=38) (actual time=843.509..843.509 rows=300270 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 25209kB Buffers: shared hit=145389 read=849 written=2 -> Nested Loop (cost=905.25..35292.17 rows=300000 width=38) (actual time=20.043..737.874 rows=300270 loops=1) Buffers: shared hit=145389 read=849 written=2 -> Nested Loop (cost=0.14..13.95 rows=5 width=30) (actual time=0.051..0.112 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=0.010..0.031 rows=25 loops=1) Buffers: shared hit=2 -> Materialize (cost=0.00..1.07 rows=1 width=4) (actual time=0.001..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=0.014..0.015 rows=1 loops=1) Filter: (r_name = 'ASIA'::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=18.164..134.618 rows=60054 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Heap Blocks: exact=145400 Buffers: shared hit=145386 read=849 written=2 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=11.809..11.809 rows=60054 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=5 read=830 written=2 -> Index Scan using pk_lineitem on lineitem (cost=0.56..3.03 rows=15 width=16) (actual time=0.014..0.015 rows=4 loops=456512) Index Cond: (l_orderkey = orders.o_orderkey) Buffers: shared hit=1999456 read=315692 written=648 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=63.930..63.930 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=0.009..38.732 rows=100000 loops=1) Buffers: shared hit=2179 Planning time: 6.835 ms Execution time: 13769.004 ms (56 rows) COMMIT; COMMIT