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 = 'UNITED KINGDOM' and n2.n_name = 'ALGERIA') or (n1.n_name = 'ALGERIA' and n2.n_name = 'UNITED KINGDOM') ) 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=2374888.17..2376796.60 rows=58721 width=64) (actual time=145653.249..145685.576 rows=4 loops=1) Buffers: shared hit=1255904 read=188049 written=7721 -> Sort (cost=2374888.17..2375034.97 rows=58721 width=64) (actual time=145643.400..145653.433 rows=57766 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: 9660kB Buffers: shared hit=1255904 read=188049 written=7721 -> Hash Join (cost=900586.29..2370237.00 rows=58721 width=64) (actual time=70336.538..145225.906 rows=57766 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (n1.n_nationkey = supplier.s_nationkey)) Buffers: shared hit=1255896 read=188049 written=7721 -> Hash Join (cost=895907.29..2335311.66 rows=1468276 width=72) (actual time=70175.301..141151.705 rows=1459506 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=1253714 read=188049 written=7721 -> Bitmap Heap Scan on lineitem (cost=386964.26..1742805.36 rows=18368140 width=20) (actual time=20644.154..64609.103 rows=18246268 loops=1) Recheck Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=941733 read=184777 written=7721 -> Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx (cost=0.00..382372.23 rows=18368140 width=0) (actual time=19943.433..19943.433 rows=18484985 loops=1) Index Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared read=49815 -> Hash (cost=493745.30..493745.30 rows=1215818 width=60) (actual time=49530.318..49530.318 rows=1202501 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 108038kB Buffers: shared hit=311981 read=3272 -> Hash Join (cost=15638.06..493745.30 rows=1215818 width=60) (actual time=1632.994..48461.835 rows=1202501 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=311981 read=3272 -> Seq Scan on orders (cost=0.00..408911.95 rows=15209895 width=8) (actual time=0.269..11612.484 rows=15015000 loops=1) Buffers: shared hit=253882 read=2931 -> Hash (cost=14139.26..14139.26 rows=119904 width=60) (actual time=1632.578..1632.578 rows=120297 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 10808kB Buffers: shared hit=58099 read=341 -> Nested Loop (cost=905.09..14139.26 rows=119904 width=60) (actual time=45.839..1525.495 rows=120297 loops=1) Buffers: shared hit=58099 read=341 -> Nested Loop (cost=0.00..28.00 rows=2 width=60) (actual time=0.082..0.544 rows=2 loops=1) Join Filter: (((n1.n_name = 'UNITED KINGDOM'::bpchar) AND (n2.n_name = 'ALGERIA'::bpchar)) OR ((n1.n_name = 'ALGERIA'::bpchar) AND (n2.n_name = 'UNITED KINGDOM'::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=0.019..0.042 rows=25 loops=1) Buffers: shared hit=2 -> Materialize (cost=0.00..1.38 rows=25 width=30) (actual time=0.001..0.005 rows=25 loops=25) Buffers: shared hit=1 -> Seq Scan on nation n2 (cost=0.00..1.25 rows=25 width=30) (actual time=0.004..0.012 rows=25 loops=1) Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=49.231..739.814 rows=60148 loops=2) Recheck Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=58096 read=341 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=35.142..35.142 rows=60148 loops=2) Index Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=3 read=332 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=159.975..159.975 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=0.009..110.961 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 145988.614 ms (53 rows) COMMIT; COMMIT