BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select supp_nation, cust_nation, l_year, sum(volume) as revenue from ( select n1.n_name as supp_nation, n2.n_name as cust_nation, extract(year from l_shipdate) as l_year, l_extendedprice * (1 - l_discount) as volume from supplier, lineitem, orders, customer, nation n1, nation n2 where s_suppkey = l_suppkey and o_orderkey = l_orderkey and c_custkey = o_custkey and s_nationkey = n1.n_nationkey and c_nationkey = n2.n_nationkey and ( (n1.n_name = 'ALGERIA' and n2.n_name = 'CHINA') or (n1.n_name = 'CHINA' and n2.n_name = 'ALGERIA') ) and l_shipdate between date '1995-01-01' and date '1996-12-31' ) as shipping group by supp_nation, cust_nation, l_year order by supp_nation, cust_nation, l_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- GroupAggregate (cost=2361363.41..2363262.32 rows=58428 width=64) (actual time=93594.120..93625.302 rows=4 loops=1) Buffers: shared hit=688385 read=746275 dirtied=51 written=1484 -> Sort (cost=2361363.41..2361509.48 rows=58428 width=64) (actual time=93582.704..93593.086 rows=57815 loops=1) Sort Key: n1.n_name, n2.n_name, (date_part('year'::text, (lineitem.l_shipdate)::timestamp without time zone)) Sort Method: quicksort Memory: 9667kB Buffers: shared hit=688385 read=746275 dirtied=51 written=1484 -> Hash Join (cost=896558.91..2356737.56 rows=58428 width=64) (actual time=55378.570..93298.701 rows=57815 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (n1.n_nationkey = supplier.s_nationkey)) Buffers: shared hit=688377 read=746275 dirtied=51 written=1484 -> Hash Join (cost=891879.91..2321968.18 rows=1460698 width=72) (actual time=55255.308..90615.326 rows=1463009 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=686195 read=746275 dirtied=51 written=1484 -> Bitmap Heap Scan on lineitem (cost=386340.66..1733296.89 rows=18273349 width=20) (actual time=17265.947..34120.169 rows=18247310 loops=1) Recheck Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=483694 read=635376 written=197 -> Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx (cost=0.00..381772.32 rows=18273349 width=0) (actual time=16579.897..16579.897 rows=18356292 loops=1) Index Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared read=49815 -> Hash (cost=490446.39..490446.39 rows=1207429 width=60) (actual time=37988.401..37988.401 rows=1202588 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 108046kB Buffers: shared hit=202501 read=110899 dirtied=51 written=1287 -> Hash Join (cost=15638.06..490446.39 rows=1207429 width=60) (actual time=1042.242..36234.024 rows=1202588 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=202501 read=110899 dirtied=51 written=1287 -> Seq Scan on orders (cost=0.00..406090.48 rows=15104948 width=8) (actual time=0.014..7007.230 rows=15015000 loops=1) Buffers: shared hit=178739 read=76302 dirtied=51 written=1280 -> Hash (cost=14139.26..14139.26 rows=119904 width=60) (actual time=1042.113..1042.113 rows=119981 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 10780kB Buffers: shared hit=23762 read=34597 written=7 -> Nested Loop (cost=905.09..14139.26 rows=119904 width=60) (actual time=21.142..763.634 rows=119981 loops=1) Buffers: shared hit=23762 read=34597 written=7 -> Nested Loop (cost=0.00..28.00 rows=2 width=60) (actual time=0.082..0.381 rows=2 loops=1) Join Filter: (((n1.n_name = 'ALGERIA'::bpchar) AND (n2.n_name = 'CHINA'::bpchar)) OR ((n1.n_name = 'CHINA'::bpchar) AND (n2.n_name = 'ALGERIA'::bpchar))) Rows Removed by Join Filter: 623 Buffers: shared hit=3 -> Index Scan using pk_nation on nation n1 (cost=0.00..12.63 rows=25 width=30) (actual time=0.010..0.025 rows=25 loops=1) Buffers: shared hit=2 -> Materialize (cost=0.00..1.38 rows=25 width=30) (actual time=0.001..0.004 rows=25 loops=25) Buffers: shared hit=1 -> Seq Scan on nation n2 (cost=0.00..1.25 rows=25 width=30) (actual time=0.005..0.010 rows=25 loops=1) Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=21.304..365.761 rows=59990 loops=2) Recheck Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=23759 read=34597 written=7 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=13.901..13.901 rows=59990 loops=2) Index Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=1 read=333 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=122.585..122.585 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=0.020..77.965 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 93663.821 ms (53 rows) COMMIT; COMMIT