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 = 'STANDARD PLATED BRASS' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1665403.36..1665405.19 rows=729 width=38) (actual time=8199.371..8199.371 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=1753297 read=213135 -> HashAggregate (cost=1665355.94..1665368.70 rows=729 width=38) (actual time=8199.312..8199.312 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1753294 read=213135 -> Hash Join (cost=43857.57..1664891.98 rows=23198 width=38) (actual time=804.418..8163.624 rows=24745 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1753294 read=213135 -> Hash Join (cost=43856.00..1664455.46 rows=23198 width=16) (actual time=804.353..8135.708 rows=24745 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1753290 read=213135 -> Hash Join (cost=4825.32..1624757.83 rows=115990 width=20) (actual time=97.923..7377.737 rows=123680 loops=1) Hash Cond: (lineitem.l_suppkey = supplier.s_suppkey) Buffers: shared hit=1607967 read=212310 -> Nested Loop (cost=396.32..1618733.97 rows=115990 width=20) (actual time=8.172..7203.788 rows=123680 loops=1) Buffers: shared hit=1607964 read=210134 -> Nested Loop (cost=395.88..1431159.57 rows=383091 width=16) (actual time=8.099..3444.957 rows=406243 loops=1) Buffers: shared hit=315028 read=159184 -> Bitmap Heap Scan on part (cost=395.32..27402.65 rows=12760 width=4) (actual time=8.033..158.377 rows=13533 loops=1) Recheck Cond: ((p_type)::text = 'STANDARD PLATED BRASS'::text) Heap Blocks: exact=11578 Buffers: shared hit=1 read=11661 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..392.13 rows=12760 width=0) (actual time=5.549..5.549 rows=13533 loops=1) Index Cond: ((p_type)::text = 'STANDARD PLATED BRASS'::text) Buffers: shared read=84 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..109.70 rows=31 width=20) (actual time=0.023..0.234 rows=30 loops=13533) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=315027 read=147523 -> Index Scan using orders_o_orderkey_o_orderdate_idx on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.009..0.009 rows=0 loops=406243) Index Cond: ((o_orderkey = lineitem.l_orderkey) AND (o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=1292936 read=50950 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=88.840..88.840 rows=100000 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 4931kB Buffers: shared hit=3 read=2176 -> Seq Scan on supplier (cost=0.00..3179.00 rows=100000 width=8) (actual time=0.003..63.224 rows=100000 loops=1) Buffers: shared hit=3 read=2176 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=702.455..702.455 rows=299493 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14626kB Buffers: shared hit=145323 read=825 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=21.239..624.223 rows=299493 loops=1) Buffers: shared hit=145323 read=825 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.047..0.111 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..0.027 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=0.013..0.014 rows=1 loops=1) Filter: (r_name = 'AFRICA'::bpchar) Rows Removed by Filter: 4 Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.11..6455.64 rows=60000 width=8) (actual time=17.177..115.224 rows=59899 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145314 Buffers: shared hit=145321 read=825 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=11.405..11.405 rows=59899 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=7 read=825 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.018..0.018 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=0.003..0.006 rows=25 loops=1) Buffers: shared hit=1 Planning time: 11.030 ms Execution time: 8200.278 ms (69 rows) COMMIT; COMMIT