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 PLATED COPPER' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2127522.15..2127523.98 rows=731 width=38) (actual time=29727.419..29727.419 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=795714 read=206944 dirtied=1429 written=1 -> HashAggregate (cost=2127474.59..2127487.38 rows=731 width=38) (actual time=29727.349..29727.350 rows=2 loops=1) Buffers: shared hit=795711 read=206944 dirtied=1429 written=1 -> Nested Loop (cost=498101.91..2127001.49 rows=23655 width=38) (actual time=22047.309..29662.827 rows=24309 loops=1) Buffers: shared hit=795711 read=206944 dirtied=1429 written=1 -> Nested Loop (cost=498101.91..2120255.08 rows=23655 width=16) (actual time=22047.238..29501.442 rows=24309 loops=1) Buffers: shared hit=747093 read=206944 dirtied=1429 written=1 -> Hash Join (cost=498101.91..2113366.68 rows=23655 width=16) (actual time=22047.199..29169.837 rows=24309 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=674025 read=206944 dirtied=1429 written=1 -> Nested Loop (cost=0.00..1613081.03 rows=389437 width=16) (actual time=1.488..5746.110 rows=398750 loops=1) Buffers: shared hit=273908 read=193481 dirtied=1429 written=1 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..45061.89 rows=12907 width=4) (actual time=0.247..256.498 rows=13291 loops=1) Index Cond: (p_type = 'MEDIUM PLATED COPPER'::text) Heap Fetches: 13291 Buffers: shared read=11439 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..121.18 rows=31 width=20) (actual time=0.042..0.398 rows=30 loops=13291) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=273908 read=182042 dirtied=1429 written=1 -> Hash (cost=486644.73..486644.73 rows=916575 width=8) (actual time=22044.870..22044.870 rows=911416 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35603kB Buffers: shared hit=400114 read=13463 -> Hash Join (cost=136763.03..486644.73 rows=916575 width=8) (actual time=4972.957..21186.215 rows=911416 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=400114 read=13463 -> Bitmap Heap Scan on orders (cost=97732.41..421262.57 rows=4582877 width=12) (actual time=3594.095..7918.463 rows=4561664 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=254788 read=12633 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..96586.69 rows=4582877 width=0) (actual time=3361.228..3361.228 rows=4584480 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=1 read=12633 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=1378.490..1378.490 rows=299838 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10542kB Buffers: shared hit=145326 read=830 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=33.547..1202.321 rows=299838 loops=1) Buffers: shared hit=145326 read=830 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.036..0.104 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=0.013..0.027 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: 1kB Buffers: shared hit=1 -> Seq Scan on region (cost=0.00..1.06 rows=1 width=4) (actual time=0.011..0.011 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=905.09..6455.63 rows=60000 width=8) (actual time=30.662..222.391 rows=59968 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=145324 read=830 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=21.394..21.394 rows=59968 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=7 read=830 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.011..0.012 rows=1 loops=24309) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73068 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.003..0.004 rows=1 loops=24309) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48618 Total runtime: 29750.650 ms (64 rows) COMMIT; COMMIT