BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'IRAQ' 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 = 'MIDDLE EAST' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'MEDIUM POLISHED TIN' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1752177.27..1752179.09 rows=729 width=38) (actual time=8132.517..8132.518 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=2060702 read=219812 -> HashAggregate (cost=1752129.85..1752142.61 rows=729 width=38) (actual time=8132.454..8132.455 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=2060699 read=219812 -> Hash Join (cost=39450.90..1751637.73 rows=24606 width=38) (actual time=640.431..8096.747 rows=24004 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=2060699 read=219812 -> Nested Loop (cost=39449.34..1751174.80 rows=24606 width=16) (actual time=640.359..8066.925 rows=24004 loops=1) Buffers: shared hit=2060695 read=219812 -> Hash Join (cost=39449.05..1743235.35 rows=24606 width=16) (actual time=640.312..7898.929 rows=24004 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1990972 read=217364 -> Nested Loop (cost=418.36..1703497.23 rows=123031 width=20) (actual time=7.871..7203.430 rows=120921 loops=1) Buffers: shared hit=1845648 read=216533 -> Nested Loop (cost=417.93..1504456.11 rows=406510 width=16) (actual time=7.704..3057.480 rows=398672 loops=1) Buffers: shared hit=305614 read=159721 -> Bitmap Heap Scan on part (cost=417.36..28370.52 rows=13540 width=4) (actual time=7.635..145.571 rows=13296 loops=1) Recheck Cond: ((p_type)::text = 'MEDIUM POLISHED TIN'::text) Heap Blocks: exact=11397 Buffers: shared hit=8 read=11457 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..413.98 rows=13540 width=0) (actual time=5.192..5.192 rows=13296 loops=1) Index Cond: ((p_type)::text = 'MEDIUM POLISHED TIN'::text) Buffers: shared read=68 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..108.71 rows=31 width=20) (actual time=0.022..0.210 rows=30 loops=13296) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=305606 read=148264 -> Index Scan using pk_orders on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.010..0.010 rows=0 loops=398672) Index Cond: (o_orderkey = lineitem.l_orderkey) Filter: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Rows Removed by Filter: 1 Buffers: shared hit=1540034 read=56812 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=628.180..628.180 rows=299838 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14638kB Buffers: shared hit=145324 read=831 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=22.753..542.823 rows=299838 loops=1) Buffers: shared hit=145324 read=831 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.038..0.106 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=0.004..0.026 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.013..0.013 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=0.007..0.008 rows=1 loops=1) Filter: (r_name = 'MIDDLE EAST'::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=18.901..98.625 rows=59968 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145317 Buffers: shared hit=145322 read=831 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=12.949..12.949 rows=59968 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=5 read=831 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.006..0.006 rows=1 loops=24004) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=69723 read=2448 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.022..0.022 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=0.005..0.010 rows=25 loops=1) Buffers: shared hit=1 Planning time: 12.409 ms Execution time: 8133.313 ms (68 rows) COMMIT; COMMIT