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 = 'EGYPT' and n2.n_name = 'CHINA') or (n1.n_name = 'CHINA' and n2.n_name = 'EGYPT') ) 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=2380423.24..2382345.51 rows=59147 width=64) (actual time=113341.643..113367.112 rows=4 loops=1) Buffers: shared hit=743552 read=700465 written=5209 -> Sort (cost=2380423.24..2380571.10 rows=59147 width=64) (actual time=113332.779..113337.116 rows=58281 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: 9732kB Buffers: shared hit=743552 read=700465 written=5209 -> Hash Join (cost=903327.47..2375735.24 rows=59147 width=64) (actual time=56292.807..112966.394 rows=58281 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (n1.n_nationkey = supplier.s_nationkey)) Buffers: shared hit=743544 read=700465 written=5209 -> Hash Join (cost=898648.47..2340595.57 rows=1478673 width=72) (actual time=56157.951..109698.631 rows=1463668 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=741362 read=700465 written=5209 -> Bitmap Heap Scan on lineitem (cost=389705.45..1747497.56 rows=18498207 width=20) (actual time=15596.163..45005.053 rows=18246268 loops=1) Recheck Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=455080 read=671430 written=3908 -> Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx (cost=0.00..385080.90 rows=18498207 width=0) (actual time=14906.010..14906.010 rows=18484985 loops=1) Index Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=3 read=49812 written=8 -> Hash (cost=493745.30..493745.30 rows=1215818 width=60) (actual time=40560.897..40560.897 rows=1203078 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 108090kB Buffers: shared hit=286282 read=29035 written=1301 -> Hash Join (cost=15638.06..493745.30 rows=1215818 width=60) (actual time=573.033..39497.905 rows=1203078 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=286282 read=29035 written=1301 -> Seq Scan on orders (cost=0.00..408911.95 rows=15209895 width=8) (actual time=0.017..8024.915 rows=15015000 loops=1) Buffers: shared hit=227946 read=28867 written=1301 -> Hash (cost=14139.26..14139.26 rows=119904 width=60) (actual time=572.859..572.859 rows=120034 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 10785kB Buffers: shared hit=58336 read=168 -> Nested Loop (cost=905.09..14139.26 rows=119904 width=60) (actual time=16.659..492.913 rows=120034 loops=1) Buffers: shared hit=58336 read=168 -> Nested Loop (cost=0.00..28.00 rows=2 width=60) (actual time=0.139..0.472 rows=2 loops=1) Join Filter: (((n1.n_name = 'EGYPT'::bpchar) AND (n2.n_name = 'CHINA'::bpchar)) OR ((n1.n_name = 'CHINA'::bpchar) AND (n2.n_name = 'EGYPT'::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=0.036..0.062 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..0.012 rows=25 loops=1) Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=27.558..227.173 rows=60017 loops=2) Recheck Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=58333 read=168 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=16.969..16.969 rows=60017 loops=2) Index Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=168 read=167 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=134.617..134.617 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=0.013..85.787 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 113400.808 ms (53 rows) COMMIT; COMMIT