BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'MOROCCO' then volume else 0 end) / sum(volume) as mkt_share from ( select extract(year from o_orderdate) as o_year, l_extendedprice * (1 - l_discount) as volume, n2.n_name as nation from part, supplier, lineitem, orders, customer, nation n1, nation n2, region where p_partkey = l_partkey and s_suppkey = l_suppkey and l_orderkey = o_orderkey and o_custkey = c_custkey and c_nationkey = n1.n_nationkey and n1.n_regionkey = r_regionkey and r_name = 'AFRICA' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'SMALL BRUSHED NICKEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2184876.78..2184878.62 rows=733 width=38) (actual time=25706.394..25706.395 rows=2 loops=1) Sort Key: (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone)) Sort Method: quicksort Memory: 25kB Buffers: shared hit=733273 read=282436 dirtied=2669 written=6348 -> HashAggregate (cost=2184829.08..2184841.90 rows=733 width=38) (actual time=25706.324..25706.325 rows=2 loops=1) Buffers: shared hit=733270 read=282436 dirtied=2669 written=6348 -> Nested Loop (cost=502214.63..2184335.64 rows=24672 width=38) (actual time=19542.026..25657.804 rows=24858 loops=1) Buffers: shared hit=733270 read=282436 dirtied=2669 written=6348 -> Nested Loop (cost=502214.63..2177299.18 rows=24672 width=16) (actual time=19541.953..25550.950 rows=24858 loops=1) Buffers: shared hit=683554 read=282436 dirtied=2669 written=6348 -> Hash Join (cost=502214.63..2170106.78 rows=24699 width=16) (actual time=19541.903..25308.491 rows=24858 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=608860 read=282436 dirtied=2669 written=6348 -> Nested Loop (cost=0.00..1665616.96 rows=405640 width=16) (actual time=0.425..4596.617 rows=404132 loops=1) Buffers: shared hit=244896 read=231299 dirtied=2669 written=6314 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46506.04 rows=13387 width=4) (actual time=0.328..178.431 rows=13487 loops=1) Index Cond: (p_type = 'SMALL BRUSHED NICKEL'::text) Heap Fetches: 13487 Buffers: shared hit=3 read=11599 written=302 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.64 rows=31 width=20) (actual time=0.030..0.316 rows=30 loops=13487) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=244893 read=219700 dirtied=2669 written=6012 -> Hash (cost=490683.81..490683.81 rows=922466 width=8) (actual time=19540.645..19540.645 rows=911003 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35587kB Buffers: shared hit=363961 read=51137 written=34 -> Hash Join (cost=139176.98..490683.81 rows=922466 width=8) (actual time=4482.409..19093.522 rows=911003 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=363961 read=51137 written=34 -> Bitmap Heap Scan on orders (cost=100146.36..425132.29 rows=4612329 width=12) (actual time=3043.041..6785.752 rows=4557089 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=253914 read=15035 written=34 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..98993.28 rows=4612329 width=0) (actual time=2913.732..2913.732 rows=4603022 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=64 read=13084 written=9 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=1439.056..1439.056 rows=299493 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10530kB Buffers: shared hit=110047 read=36102 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=31.702..1309.571 rows=299493 loops=1) Buffers: shared hit=110047 read=36102 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.034..0.082 rows=5 loops=1) Hash Cond: (n1.n_regionkey = region.r_regionkey) Buffers: shared hit=2 -> Seq Scan on nation n1 (cost=0.00..1.25 rows=25 width=8) (actual time=0.006..0.016 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.015..0.015 rows=1 loops=1) Buckets: 1024 Batches: 1 Memory Usage: 1kB Buffers: shared hit=1 -> Seq Scan on region (cost=0.00..1.06 rows=1 width=4) (actual time=0.011..0.013 rows=1 loops=1) Filter: (r_name = 'AFRICA'::bpchar) Rows Removed by Filter: 4 Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=23.310..246.346 rows=59899 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=110045 read=36102 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=15.671..15.671 rows=59899 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=7 read=826 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.008..0.008 rows=1 loops=24858) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=74694 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.002..0.002 rows=1 loops=24858) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=49716 Total runtime: 25719.659 ms (64 rows) COMMIT; COMMIT