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 '1996-01-01' and o_orderdate < date '1996-01-01' + interval '1 year' group by n_name order by revenue desc; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1866618.41..1866618.47 rows=25 width=34) (actual time=14149.885..14149.885 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=2424668 read=307039 dirtied=283 written=587 -> HashAggregate (cost=1866617.58..1866617.83 rows=25 width=34) (actual time=14149.821..14149.824 rows=5 loops=1) Group Key: nation.n_name Buffers: shared hit=2424665 read=307039 dirtied=283 written=587 -> Hash Join (cost=93113.38..1865889.65 rows=72793 width=34) (actual time=2754.840..14070.106 rows=73108 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=2424665 read=307039 dirtied=283 written=587 -> Nested Loop (cost=88434.38..1846833.59 rows=1819883 width=46) (actual time=2686.391..13349.598 rows=1829811 loops=1) Buffers: shared hit=2422483 read=307039 dirtied=283 written=587 -> Hash Join (cost=88433.81..391197.09 rows=455087 width=38) (actual time=2686.316..6762.690 rows=457726 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=296480 read=111810 dirtied=252 written=193 -> Bitmap Heap Scan on orders (cost=49391.64..339071.17 rows=2275435 width=8) (actual time=1807.001..4708.293 rows=2283984 loops=1) Recheck Cond: ((o_orderdate >= '1996-01-01'::date) AND (o_orderdate < '1997-01-01 00:00:00'::timestamp without time zone)) Heap Blocks: exact=255531 Buffers: shared hit=152651 read=109462 dirtied=252 written=182 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..48822.79 rows=2275435 width=0) (actual time=1712.845..1712.845 rows=2302185 loops=1) Index Cond: ((o_orderdate >= '1996-01-01'::date) AND (o_orderdate < '1997-01-01 00:00:00'::timestamp without time zone)) Buffers: shared read=6582 written=20 -> Hash (cost=35292.17..35292.17 rows=300000 width=38) (actual time=875.370..875.370 rows=300963 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 25258kB Buffers: shared hit=143829 read=2348 written=11 -> Nested Loop (cost=905.25..35292.17 rows=300000 width=38) (actual time=21.546..745.622 rows=300963 loops=1) Buffers: shared hit=143829 read=2348 written=11 -> Nested Loop (cost=0.14..13.95 rows=5 width=30) (actual time=0.051..0.114 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..0.038 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=0.016..0.017 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=19.298..136.090 rows=60193 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Heap Blocks: exact=145336 Buffers: shared hit=143826 read=2348 written=11 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=12.613..12.613 rows=60193 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=6 read=832 written=5 -> Index Scan using pk_lineitem on lineitem (cost=0.56..3.05 rows=15 width=16) (actual time=0.011..0.013 rows=4 loops=457726) Index Cond: (l_orderkey = orders.o_orderkey) Buffers: shared hit=2126003 read=195229 dirtied=31 written=394 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=67.719..67.719 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=0.011..40.261 rows=100000 loops=1) Buffers: shared hit=2179 Planning time: 6.672 ms Execution time: 14152.961 ms (56 rows) COMMIT; COMMIT