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=1863675.61..1863675.67 rows=25 width=34) (actual time=12488.526..12488.527 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=2413534 read=310767 written=122 -> HashAggregate (cost=1863674.78..1863675.03 rows=25 width=34) (actual time=12488.455..12488.455 rows=5 loops=1) Group Key: nation.n_name Buffers: shared hit=2413531 read=310767 written=122 -> Hash Join (cost=92251.32..1862942.23 rows=73255 width=34) (actual time=2095.493..12407.838 rows=73264 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=2413531 read=310767 written=122 -> Nested Loop (cost=87572.32..1843795.76 rows=1831322 width=46) (actual time=2028.465..11707.005 rows=1827313 loops=1) Buffers: shared hit=2411349 read=310767 written=122 -> Hash Join (cost=87571.75..389616.47 rows=457935 width=38) (actual time=2028.436..5589.092 rows=456500 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=280125 read=126864 written=99 -> Bitmap Heap Scan on orders (cost=48529.58..337408.68 rows=2289673 width=8) (actual time=913.931..3517.963 rows=2277722 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=254514 Buffers: shared hit=169992 read=90759 written=22 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..47957.16 rows=2289673 width=0) (actual time=822.247..822.247 rows=2286881 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=6236 written=7 -> Hash (cost=35292.17..35292.17 rows=300000 width=38) (actual time=1110.425..1110.425 rows=300270 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 25209kB Buffers: shared hit=110133 read=36105 written=77 -> Nested Loop (cost=905.25..35292.17 rows=300000 width=38) (actual time=20.907..996.119 rows=300270 loops=1) Buffers: shared hit=110133 read=36105 written=77 -> Nested Loop (cost=0.14..13.95 rows=5 width=30) (actual time=0.049..0.109 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=0.008..0.028 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=0.015..0.016 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=18.142..186.159 rows=60054 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Heap Blocks: exact=145400 Buffers: shared hit=110130 read=36105 written=77 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=11.820..11.820 rows=60054 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=5 read=830 written=1 -> Index Scan using pk_lineitem on lineitem (cost=0.56..3.03 rows=15 width=16) (actual time=0.010..0.012 rows=4 loops=456500) Index Cond: (l_orderkey = orders.o_orderkey) Buffers: shared hit=2131224 read=183903 written=23 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=66.286..66.286 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=0.012..39.022 rows=100000 loops=1) Buffers: shared hit=2179 Planning time: 6.545 ms Execution time: 12490.957 ms (56 rows) COMMIT; COMMIT