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 = 'SAUDI ARABIA' and n2.n_name = 'VIETNAM') or (n1.n_name = 'VIETNAM' and n2.n_name = 'SAUDI ARABIA') ) 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=2363905.79..2365810.91 rows=58619 width=64) (actual time=97163.880..97192.981 rows=4 loops=1) Buffers: shared hit=728960 read=705771 written=11586 -> Sort (cost=2363905.79..2364052.34 rows=58619 width=64) (actual time=97154.296..97162.695 rows=58478 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: 9760kB Buffers: shared hit=728960 read=705771 written=11586 -> Hash Join (cost=897819.00..2359263.44 rows=58619 width=64) (actual time=46655.126..96752.809 rows=58478 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (n1.n_nationkey = supplier.s_nationkey)) Buffers: shared hit=728952 read=705771 written=11586 -> Hash Join (cost=893140.00..2324395.71 rows=1465472 width=72) (actual time=46520.712..92920.258 rows=1454641 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=726786 read=705755 written=11586 -> Bitmap Heap Scan on lineitem (cost=387600.76..1735452.75 rows=18333066 width=20) (actual time=14915.114..40146.511 rows=18247310 loops=1) Recheck Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=460945 read=658125 written=11578 -> Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx (cost=0.00..383017.49 rows=18333066 width=0) (actual time=14243.856..14243.856 rows=18356292 loops=1) Index Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=4 read=49811 written=102 -> Hash (cost=490446.39..490446.39 rows=1207429 width=60) (actual time=31604.770..31604.770 rows=1196207 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 107472kB Buffers: shared hit=265841 read=47630 written=8 -> Hash Join (cost=15638.06..490446.39 rows=1207429 width=60) (actual time=470.768..30810.162 rows=1196207 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=265841 read=47630 written=8 -> Seq Scan on orders (cost=0.00..406090.48 rows=15104948 width=8) (actual time=0.017..5928.098 rows=15015000 loops=1) Buffers: shared hit=207744 read=47297 written=8 -> Hash (cost=14139.26..14139.26 rows=119904 width=60) (actual time=470.620..470.620 rows=119800 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 10764kB Buffers: shared hit=58097 read=333 -> Nested Loop (cost=905.09..14139.26 rows=119904 width=60) (actual time=20.849..400.374 rows=119800 loops=1) Buffers: shared hit=58097 read=333 -> Nested Loop (cost=0.00..28.00 rows=2 width=60) (actual time=0.235..0.335 rows=2 loops=1) Join Filter: (((n1.n_name = 'SAUDI ARABIA'::bpchar) AND (n2.n_name = 'VIETNAM'::bpchar)) OR ((n1.n_name = 'VIETNAM'::bpchar) AND (n2.n_name = 'SAUDI ARABIA'::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=0.018..0.032 rows=25 loops=1) Buffers: shared hit=2 -> Materialize (cost=0.00..1.38 rows=25 width=30) (actual time=0.001..0.003 rows=25 loops=25) Buffers: shared hit=1 -> Seq Scan on nation n2 (cost=0.00..1.25 rows=25 width=30) (actual time=0.003..0.007 rows=25 loops=1) Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=24.785..183.043 rows=59900 loops=2) Recheck Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=58094 read=333 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=16.565..16.565 rows=59900 loops=2) Index Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=2 read=333 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=133.365..133.365 rows=100000 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 3907kB Buffers: shared hit=2163 read=16 -> Seq Scan on supplier (cost=0.00..3179.00 rows=100000 width=8) (actual time=0.015..91.873 rows=100000 loops=1) Buffers: shared hit=2163 read=16 Total runtime: 97213.722 ms (53 rows) COMMIT; COMMIT