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 = 'KENYA') or (n1.n_name = 'KENYA' 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=2359120.13..2361023.46 rows=58564 width=64) (actual time=115923.096..115961.575 rows=4 loops=1) Buffers: shared hit=503729 read=926968 dirtied=1054 written=17514 -> Sort (cost=2359120.13..2359266.54 rows=58564 width=64) (actual time=115914.499..115923.033 rows=57945 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: 9685kB Buffers: shared hit=503729 read=926968 dirtied=1054 written=17514 -> Hash Join (cost=896594.13..2354482.53 rows=58564 width=64) (actual time=51729.607..115538.635 rows=57945 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (n1.n_nationkey = supplier.s_nationkey)) Buffers: shared hit=503721 read=926968 dirtied=1054 written=17514 -> Hash Join (cost=891915.13..2319643.23 rows=1464092 width=72) (actual time=51586.626..111369.818 rows=1457235 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=501539 read=926968 dirtied=1054 written=17514 -> Bitmap Heap Scan on lineitem (cost=387835.75..1732238.70 rows=18315797 width=20) (actual time=18131.690..51144.201 rows=18247629 loops=1) Recheck Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared hit=223985 read=891906 dirtied=1054 written=17514 -> Bitmap Index Scan on lineitem_l_shipdate_l_suppkey__idx (cost=0.00..383256.80 rows=18315797 width=0) (actual time=17380.712..17380.712 rows=18302308 loops=1) Index Cond: ((l_shipdate >= '1995-01-01'::date) AND (l_shipdate <= '1996-12-31'::date)) Buffers: shared read=49815 -> Hash (cost=489031.49..489031.49 rows=1203831 width=60) (actual time=33453.857..33453.857 rows=1196927 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 107537kB Buffers: shared hit=277554 read=35062 -> Hash Join (cost=15638.06..489031.49 rows=1203831 width=60) (actual time=1783.700..32270.719 rows=1196927 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=277554 read=35062 -> Seq Scan on orders (cost=0.00..404880.36 rows=15059936 width=8) (actual time=0.021..5728.132 rows=15015000 loops=1) Buffers: shared hit=253828 read=453 -> Hash (cost=14139.26..14139.26 rows=119904 width=60) (actual time=1783.546..1783.546 rows=119392 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 10727kB Buffers: shared hit=23726 read=34609 -> Nested Loop (cost=905.09..14139.26 rows=119904 width=60) (actual time=21.013..1680.860 rows=119392 loops=1) Buffers: shared hit=23726 read=34609 -> Nested Loop (cost=0.00..28.00 rows=2 width=60) (actual time=0.091..0.361 rows=2 loops=1) Join Filter: (((n1.n_name = 'ALGERIA'::bpchar) AND (n2.n_name = 'KENYA'::bpchar)) OR ((n1.n_name = 'KENYA'::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=0.024..0.040 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=0.007..0.016 rows=25 loops=1) Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=28.000..816.111 rows=59696 loops=2) Recheck Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=23723 read=34609 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=19.597..19.597 rows=59696 loops=2) Index Cond: (c_nationkey = n2.n_nationkey) Buffers: shared hit=1 read=331 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=142.106..142.106 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=0.019..95.982 rows=100000 loops=1) Buffers: shared hit=2179 Total runtime: 116003.769 ms (53 rows) COMMIT; COMMIT