BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'GERMANY' 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 = 'LARGE PLATED BRASS' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1728496.73..1728498.55 rows=729 width=38) (actual time=11124.033..11124.033 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=1986384 read=312723 dirtied=2413 written=1073 -> HashAggregate (cost=1728449.31..1728462.07 rows=729 width=38) (actual time=11123.976..11123.977 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1986381 read=312723 dirtied=2413 written=1073 -> Hash Join (cost=39444.94..1727962.05 rows=24363 width=38) (actual time=1182.516..11085.181 rows=24170 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1986381 read=312723 dirtied=2413 written=1073 -> Nested Loop (cost=39443.38..1727503.68 rows=24363 width=16) (actual time=1182.461..11051.330 rows=24170 loops=1) Buffers: shared hit=1986377 read=312723 dirtied=2413 written=1073 -> Hash Join (cost=39443.09..1719642.66 rows=24363 width=16) (actual time=1182.435..10869.161 rows=24170 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1913725 read=312723 dirtied=2413 written=1073 -> Nested Loop (cost=412.40..1679911.54 rows=121815 width=20) (actual time=6.975..9610.417 rows=121168 loops=1) Buffers: shared hit=1803655 read=276617 dirtied=2413 written=887 -> Nested Loop (cost=411.97..1482826.83 rows=402494 width=16) (actual time=6.914..4081.113 rows=401687 loops=1) Buffers: shared hit=259723 read=211734 dirtied=2265 written=707 -> Bitmap Heap Scan on part (cost=411.40..28063.46 rows=13287 width=4) (actual time=6.856..185.779 rows=13404 loops=1) Recheck Cond: ((p_type)::text = 'LARGE PLATED BRASS'::text) Heap Blocks: exact=11418 Buffers: shared read=11488 written=37 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..408.08 rows=13287 width=0) (actual time=4.613..4.613 rows=13404 loops=1) Index Cond: ((p_type)::text = 'LARGE PLATED BRASS'::text) Buffers: shared read=70 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..109.18 rows=31 width=20) (actual time=0.027..0.281 rows=30 loops=13404) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=259723 read=200246 dirtied=2265 written=670 -> Index Scan using pk_orders on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.013..0.013 rows=0 loops=401687) 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=1543932 read=64883 dirtied=148 written=180 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=1171.043..1171.043 rows=300963 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14677kB Buffers: shared hit=110070 read=36106 written=186 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=21.456..1053.077 rows=300963 loops=1) Buffers: shared hit=110070 read=36106 written=186 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.083..0.114 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..0.018 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.052..0.052 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=0.043..0.044 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=19.443..199.074 rows=60193 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145336 Buffers: shared hit=110068 read=36106 written=186 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=12.692..12.692 rows=60193 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=6 read=832 written=5 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.006..0.007 rows=1 loops=24170) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72652 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.020..0.020 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..0.009 rows=25 loops=1) Buffers: shared hit=1 Planning time: 7.691 ms Execution time: 11124.922 ms (68 rows) COMMIT; COMMIT