BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'ROMANIA' 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 = 'EUROPE' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'SMALL BRUSHED TIN' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1812022.52..1812024.34 rows=729 width=38) (actual time=11430.344..11430.345 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=1730044 read=299867 dirtied=818 written=9522 -> HashAggregate (cost=1811975.10..1811987.85 rows=729 width=38) (actual time=11430.273..11430.274 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1730041 read=299867 dirtied=818 written=9522 -> Hash Join (cost=39471.03..1811460.84 rows=25713 width=38) (actual time=1168.702..11390.702 rows=24520 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1730041 read=299867 dirtied=818 written=9522 -> Nested Loop (cost=39469.47..1810977.16 rows=25713 width=16) (actual time=1168.606..11354.092 rows=24520 loops=1) Buffers: shared hit=1730037 read=299867 dirtied=818 written=9522 -> Hash Join (cost=39469.18..1802680.53 rows=25713 width=16) (actual time=1168.580..11138.964 rows=24520 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1656359 read=299867 dirtied=818 written=9522 -> Nested Loop (cost=438.49..1762910.60 rows=128564 width=20) (actual time=7.375..9864.947 rows=122142 loops=1) Buffers: shared hit=1546289 read=263761 dirtied=818 written=9522 -> Nested Loop (cost=438.06..1554996.42 rows=424620 width=16) (actual time=7.192..4901.784 rows=404233 loops=1) Buffers: shared hit=251438 read=222440 dirtied=818 written=8086 -> Bitmap Heap Scan on part (cost=437.49..29008.84 rows=14073 width=4) (actual time=7.103..177.651 rows=13459 loops=1) Recheck Cond: ((p_type)::text = 'SMALL BRUSHED TIN'::text) Heap Blocks: exact=11466 Buffers: shared hit=2269 read=9266 written=371 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..433.98 rows=14073 width=0) (actual time=4.739..4.739 rows=13459 loops=1) Index Cond: ((p_type)::text = 'SMALL BRUSHED TIN'::text) Buffers: shared read=69 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..108.12 rows=31 width=20) (actual time=0.031..0.341 rows=30 loops=13459) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=249169 read=213174 dirtied=818 written=7715 -> 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=404233) Index Cond: ((o_orderkey = lineitem.l_orderkey) AND (o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=1294851 read=41321 written=1436 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=1154.410..1154.410 rows=300963 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14677kB Buffers: shared hit=110070 read=36106 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=22.667..1038.223 rows=300963 loops=1) Buffers: shared hit=110070 read=36106 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.074..0.103 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=0.007..0.014 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.024..0.024 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=0.016..0.017 rows=1 loops=1) Filter: (r_name = 'EUROPE'::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=20.106..196.267 rows=60193 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145336 Buffers: shared hit=110068 read=36106 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=13.196..13.196 rows=60193 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=6 read=832 -> 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=24520) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73678 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.027..0.027 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: 8.680 ms Execution time: 11431.592 ms (66 rows) COMMIT; COMMIT