BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'RUSSIA' 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 POLISHED STEEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2203099.75..2203101.58 rows=733 width=38) (actual time=32509.180..32509.180 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=816577 read=183891 dirtied=1200 written=3059 -> HashAggregate (cost=2203052.04..2203064.86 rows=733 width=38) (actual time=32509.113..32509.115 rows=2 loops=1) Buffers: shared hit=816574 read=183891 dirtied=1200 written=3059 -> Nested Loop (cost=498476.06..2202552.62 rows=24971 width=38) (actual time=21469.656..32425.742 rows=24295 loops=1) Buffers: shared hit=816574 read=183891 dirtied=1200 written=3059 -> Nested Loop (cost=498476.06..2195430.89 rows=24971 width=16) (actual time=21469.585..32136.133 rows=24295 loops=1) Buffers: shared hit=767984 read=183891 dirtied=1200 written=3059 -> Hash Join (cost=498476.06..2188159.26 rows=24971 width=16) (actual time=21469.538..31540.560 rows=24295 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=694933 read=183891 dirtied=1200 written=3059 -> Nested Loop (cost=0.00..1687381.76 rows=410347 width=16) (actual time=0.297..8654.400 rows=396922 loops=1) Buffers: shared hit=282162 read=183061 dirtied=1200 written=3059 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..47138.02 rows=13600 width=4) (actual time=0.242..273.990 rows=13207 loops=1) Index Cond: (p_type = 'SMALL POLISHED STEEL'::text) Heap Fetches: 13207 Buffers: shared hit=4377 read=7048 written=2 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.30 rows=31 width=20) (actual time=0.063..0.616 rows=30 loops=13207) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=277785 read=176013 dirtied=1200 written=3057 -> Hash (cost=486997.81..486997.81 rows=918260 width=8) (actual time=21468.388..21468.388 rows=913799 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35696kB Buffers: shared hit=412768 read=830 -> Hash Join (cost=136941.36..486997.81 rows=918260 width=8) (actual time=3195.036..20179.952 rows=913799 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=412768 read=830 -> Bitmap Heap Scan on orders (cost=97910.74..421567.22 rows=4591299 width=12) (actual time=1417.344..6007.745 rows=4561664 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=267421 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..96762.91 rows=4591299 width=0) (actual time=1329.448..1329.448 rows=4584480 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=12634 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=1777.350..1777.350 rows=300963 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10581kB Buffers: shared hit=145347 read=830 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=30.460..1523.599 rows=300963 loops=1) Buffers: shared hit=145347 read=830 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.026..0.087 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..0.021 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: 1kB Buffers: shared hit=1 -> Seq Scan on region (cost=0.00..1.06 rows=1 width=4) (actual time=0.012..0.013 rows=1 loops=1) Filter: (r_name = 'EUROPE'::bpchar) Rows Removed by Filter: 4 Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=905.09..6455.63 rows=60000 width=8) (actual time=35.796..283.783 rows=60193 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=145345 read=830 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=25.127..25.127 rows=60193 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=9 read=830 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.021..0.022 rows=1 loops=24295) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73051 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.008..0.008 rows=1 loops=24295) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48590 Total runtime: 32528.167 ms (64 rows) COMMIT; COMMIT