BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'PERU' 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 = 'AMERICA' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'PROMO PLATED COPPER' ) as all_nations group by o_year order by o_year; QUERY PLAN ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1772621.35..1772623.17 rows=729 width=38) (actual time=10962.708..10962.709 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=2063468 read=259104 dirtied=2253 written=13 -> HashAggregate (cost=1772573.93..1772586.69 rows=729 width=38) (actual time=10962.668..10962.669 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=2063465 read=259104 dirtied=2253 written=13 -> Hash Join (cost=38755.66..1772071.71 rows=25111 width=38) (actual time=2221.517..10923.617 rows=24143 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=2063465 read=259104 dirtied=2253 written=13 -> Nested Loop (cost=38754.10..1771599.31 rows=25111 width=16) (actual time=2221.467..10885.713 rows=24143 loops=1) Buffers: shared hit=2063461 read=259104 dirtied=2253 written=13 -> Hash Join (cost=38753.80..1763483.72 rows=25152 width=16) (actual time=2221.449..10746.237 rows=24143 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1990912 read=259104 dirtied=2253 written=13 -> Nested Loop (cost=423.66..1724430.44 rows=125762 width=20) (actual time=6.860..8453.508 rows=121874 loops=1) Buffers: shared hit=1847955 read=225663 dirtied=2253 written=13 -> Nested Loop (cost=423.22..1521116.27 rows=415216 width=16) (actual time=6.703..4736.727 rows=400446 loops=1) Buffers: shared hit=255937 read=213668 dirtied=2246 written=13 -> Bitmap Heap Scan on part (cost=422.66..28572.95 rows=13707 width=4) (actual time=6.635..179.885 rows=13349 loops=1) Recheck Cond: ((p_type)::text = 'PROMO PLATED COPPER'::text) Heap Blocks: exact=11436 Buffers: shared hit=91 read=11413 written=1 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..419.23 rows=13707 width=0) (actual time=4.386..4.386 rows=13349 loops=1) Index Cond: ((p_type)::text = 'PROMO PLATED COPPER'::text) Buffers: shared read=68 -> Index Scan using lineitem_l_partkey_l_quantity_idx on lineitem (cost=0.56..108.58 rows=31 width=20) (actual time=0.027..0.332 rows=30 loops=13349) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=255846 read=202255 dirtied=2246 written=12 -> Index Scan using pk_orders on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.009..0.009 rows=0 loops=400446) 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=1592018 read=11995 dirtied=7 -> Hash (cost=34580.15..34580.15 rows=300000 width=4) (actual time=2212.381..2212.381 rows=299436 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14624kB Buffers: shared hit=142957 read=33441 -> Nested Loop (cost=766.08..34580.15 rows=300000 width=4) (actual time=4.057..2120.094 rows=299436 loops=1) Buffers: shared hit=142957 read=33441 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.030..0.051 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..0.006 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.014..0.014 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=0.008..0.009 rows=1 loops=1) Filter: (r_name = 'AMERICA'::bpchar) Rows Removed by Filter: 4 Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=765.00..6315.54 rows=60000 width=8) (actual time=3.960..414.188 rows=59887 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Rows Removed by Index Recheck: 1440113 Heap Blocks: lossy=176390 Buffers: shared hit=142955 read=33441 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_brin_idx (cost=0.00..750.00 rows=60000 width=0) (actual time=3.926..3.926 rows=353280 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=4 read=2 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.005..0.005 rows=1 loops=24143) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72549 -> 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=0.004..0.006 rows=25 loops=1) Buffers: shared hit=1 Planning time: 6.633 ms Execution time: 10963.450 ms (69 rows) COMMIT; COMMIT