BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'MOZAMBIQUE' 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 = 'LARGE BRUSHED TIN' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2165593.94..2165595.77 rows=733 width=38) (actual time=32155.130..32155.131 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=794722 read=203700 dirtied=1270 written=36 -> HashAggregate (cost=2165546.23..2165559.06 rows=733 width=38) (actual time=32154.963..32154.964 rows=2 loops=1) Buffers: shared hit=794719 read=203700 dirtied=1270 written=36 -> Nested Loop (cost=498476.06..2165059.55 rows=24334 width=38) (actual time=23489.895..32085.815 rows=24061 loops=1) Buffers: shared hit=794719 read=203700 dirtied=1270 written=36 -> Nested Loop (cost=498476.06..2158119.49 rows=24334 width=16) (actual time=23489.834..31873.746 rows=24061 loops=1) Buffers: shared hit=746597 read=203700 dirtied=1270 written=36 -> Hash Join (cost=498476.06..2151033.36 rows=24334 width=16) (actual time=23489.784..31502.590 rows=24061 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=674255 read=203700 dirtied=1270 written=36 -> Nested Loop (cost=0.00..1650314.58 rows=399877 width=16) (actual time=0.814..6767.122 rows=396372 loops=1) Buffers: shared hit=273813 read=190569 dirtied=1270 written=36 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46103.97 rows=13253 width=4) (actual time=0.504..271.423 rows=13197 loops=1) Index Cond: (p_type = 'LARGE BRUSHED TIN'::text) Heap Fetches: 13197 Buffers: shared hit=1108 read=10232 written=2 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.74 rows=31 width=20) (actual time=0.051..0.476 rows=30 loops=13197) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=272705 read=180337 dirtied=1270 written=34 -> Hash (cost=486997.81..486997.81 rows=918260 width=8) (actual time=23487.676..23487.676 rows=911930 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35623kB Buffers: shared hit=400439 read=13131 -> Hash Join (cost=136941.36..486997.81 rows=918260 width=8) (actual time=6786.507..22654.979 rows=911930 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=400439 read=13131 -> Bitmap Heap Scan on orders (cost=97910.74..421567.22 rows=4591299 width=12) (actual time=3895.962..8318.899 rows=4561664 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=254787 read=12634 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..96762.91 rows=4591299 width=0) (actual time=3782.074..3782.074 rows=4584480 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=12634 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=2890.217..2890.217 rows=299493 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10530kB Buffers: shared hit=145652 read=497 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=37.131..2686.188 rows=299493 loops=1) Buffers: shared hit=145652 read=497 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.040..0.112 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=0.008..0.023 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.018..0.018 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=0.014..0.016 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=37.967..516.033 rows=59899 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=145650 read=497 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=28.798..28.798 rows=59899 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=341 read=492 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.013..0.013 rows=1 loops=24061) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72342 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.005..0.006 rows=1 loops=24061) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48122 Total runtime: 32179.148 ms (64 rows) COMMIT; COMMIT