BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'CHINA' 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 = 'ASIA' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'SMALL PLATED NICKEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1784921.41..1784923.24 rows=732 width=38) (actual time=11085.952..11085.953 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=1792927 read=233751 dirtied=363 written=6900 -> HashAggregate (cost=1784873.77..1784886.58 rows=732 width=38) (actual time=11085.873..11085.874 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1792924 read=233751 dirtied=363 written=6900 -> Hash Join (cost=39461.17..1784367.55 rows=25311 width=38) (actual time=1347.601..11039.440 rows=24651 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1792924 read=233751 dirtied=363 written=6900 -> Nested Loop (cost=39459.61..1783891.41 rows=25311 width=16) (actual time=1347.521..10996.678 rows=24651 loops=1) Buffers: shared hit=1792920 read=233751 dirtied=363 written=6900 -> Hash Join (cost=39459.32..1775724.48 rows=25311 width=16) (actual time=1347.499..10751.130 rows=24651 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1718845 read=233751 dirtied=363 written=6900 -> Nested Loop (cost=428.63..1735966.11 rows=126553 width=20) (actual time=9.857..9303.375 rows=122425 loops=1) Buffers: shared hit=1605829 read=200530 dirtied=363 written=6267 -> Nested Loop (cost=428.20..1532170.95 rows=416218 width=16) (actual time=9.795..4222.064 rows=403424 loops=1) Buffers: shared hit=319082 read=153133 dirtied=363 written=4662 -> Bitmap Heap Scan on part (cost=427.63..28724.37 rows=13833 width=4) (actual time=9.711..181.579 rows=13442 loops=1) Recheck Cond: ((p_type)::text = 'SMALL PLATED NICKEL'::text) Heap Blocks: exact=11434 Buffers: shared hit=2615 read=8888 written=289 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..424.18 rows=13833 width=0) (actual time=6.717..6.717 rows=13442 loops=1) Index Cond: ((p_type)::text = 'SMALL PLATED NICKEL'::text) Buffers: shared read=69 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..108.38 rows=31 width=20) (actual time=0.029..0.289 rows=30 loops=13442) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=316467 read=144245 dirtied=363 written=4373 -> 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=403424) Index Cond: ((o_orderkey = lineitem.l_orderkey) AND (o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=1286747 read=47397 written=1605 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=1332.544..1332.544 rows=300270 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14653kB Buffers: shared hit=113016 read=33221 written=633 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=32.044..1210.040 rows=300270 loops=1) Buffers: shared hit=113016 read=33221 written=633 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.087..0.119 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=0.009..0.015 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.034..0.034 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=0.020..0.021 rows=1 loops=1) Filter: (r_name = 'ASIA'::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=22.492..229.121 rows=60054 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145400 Buffers: shared hit=113014 read=33221 written=633 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=14.664..14.664 rows=60054 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=5 read=830 written=22 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.008..0.009 rows=1 loops=24651) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=74075 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.032..0.032 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=0.006..0.014 rows=25 loops=1) Buffers: shared hit=1 Planning time: 11.953 ms Execution time: 11087.211 ms (66 rows) COMMIT; COMMIT