BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'BRAZIL' 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 = 'AMERICA' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'MEDIUM BURNISHED TIN' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1678571.92..1678573.74 rows=729 width=38) (actual time=11062.606..11062.606 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=1740289 read=259711 dirtied=846 written=7827 -> HashAggregate (cost=1678524.50..1678537.26 rows=729 width=38) (actual time=11062.548..11062.550 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1740286 read=259711 dirtied=846 written=7827 -> Hash Join (cost=39429.53..1678054.96 rows=23477 width=38) (actual time=887.184..11022.642 rows=23761 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1740286 read=259711 dirtied=846 written=7827 -> Nested Loop (cost=39427.97..1677613.20 rows=23477 width=16) (actual time=887.118..10986.897 rows=23761 loops=1) Buffers: shared hit=1740282 read=259711 dirtied=846 written=7827 -> Hash Join (cost=39427.68..1670038.05 rows=23477 width=16) (actual time=887.065..10773.604 rows=23761 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1668900 read=259711 dirtied=846 written=7827 -> Nested Loop (cost=396.99..1630332.39 rows=117387 width=20) (actual time=7.783..9814.191 rows=120469 loops=1) Buffers: shared hit=1525252 read=257422 dirtied=846 written=7716 -> Nested Loop (cost=396.56..1440494.58 rows=387706 width=16) (actual time=7.724..4909.631 rows=397982 loops=1) Buffers: shared hit=248294 read=218574 dirtied=846 written=6606 -> Bitmap Heap Scan on part (cost=395.99..27511.61 rows=12847 width=4) (actual time=7.619..170.500 rows=13268 loops=1) Recheck Cond: ((p_type)::text = 'MEDIUM BURNISHED TIN'::text) Heap Blocks: exact=11330 Buffers: shared hit=2875 read=8538 written=311 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..392.78 rows=12847 width=0) (actual time=5.286..5.286 rows=13268 loops=1) Index Cond: ((p_type)::text = 'MEDIUM BURNISHED TIN'::text) Buffers: shared read=83 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..109.68 rows=31 width=20) (actual time=0.032..0.347 rows=30 loops=13268) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=245419 read=210036 dirtied=846 written=6295 -> Index Scan using orders_o_orderkey_o_orderdate_idx on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.012..0.012 rows=0 loops=397982) Index Cond: ((o_orderkey = lineitem.l_orderkey) AND (o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=1276958 read=38848 written=1110 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=876.837..876.837 rows=299436 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14624kB Buffers: shared hit=143648 read=2289 written=111 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=21.280..783.162 rows=299436 loops=1) Buffers: shared hit=143648 read=2289 written=111 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.045..0.076 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..0.016 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.020..0.020 rows=1 loops=1) Buckets: 1024 Batches: 1 Memory Usage: 9kB Buffers: shared hit=1 -> Seq Scan on region (cost=0.00..1.06 rows=1 width=4) (actual time=0.014..0.015 rows=1 loops=1) Filter: (r_name = 'AMERICA'::bpchar) Rows Removed by Filter: 4 Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.11..6455.64 rows=60000 width=8) (actual time=19.432..145.265 rows=59887 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145102 Buffers: shared hit=143646 read=2289 written=111 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=12.587..12.587 rows=59887 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=8 read=825 written=33 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.007..0.008 rows=1 loops=23761) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=71382 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.021..0.021 rows=25 loops=1) Buckets: 1024 Batches: 1 Memory Usage: 10kB Buffers: shared hit=1 -> Seq Scan on nation n2 (cost=0.00..1.25 rows=25 width=30) (actual time=0.004..0.007 rows=25 loops=1) Buffers: shared hit=1 Planning time: 8.568 ms Execution time: 11063.427 ms (66 rows) COMMIT; COMMIT