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 = 'MEDIUM PLATED NICKEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1734203.56..1734205.37 rows=727 width=38) (actual time=11761.665..11761.666 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=1702523 read=298881 dirtied=202 written=7875 -> HashAggregate (cost=1734156.28..1734169.00 rows=727 width=38) (actual time=11761.607..11761.608 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1702520 read=298881 dirtied=202 written=7875 -> Hash Join (cost=39453.87..1733668.02 rows=24413 width=38) (actual time=1099.227..11718.632 rows=24410 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1702520 read=298881 dirtied=202 written=7875 -> Nested Loop (cost=39452.31..1733208.71 rows=24413 width=16) (actual time=1099.144..11679.368 rows=24410 loops=1) Buffers: shared hit=1702516 read=298881 dirtied=202 written=7875 -> Hash Join (cost=39452.01..1725331.55 rows=24413 width=16) (actual time=1099.120..11460.500 rows=24410 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1629174 read=298881 dirtied=202 written=7875 -> Nested Loop (cost=421.33..1685598.99 rows=122066 width=20) (actual time=7.571..10233.339 rows=121258 loops=1) Buffers: shared hit=1519049 read=262830 dirtied=202 written=6589 -> Nested Loop (cost=420.89..1487783.36 rows=403999 width=16) (actual time=7.412..5267.281 rows=397604 loops=1) Buffers: shared hit=240493 read=225906 dirtied=202 written=5441 -> Bitmap Heap Scan on part (cost=416.18..28188.45 rows=13387 width=4) (actual time=7.272..154.537 rows=13254 loops=1) Recheck Cond: ((p_type)::text = 'MEDIUM PLATED NICKEL'::text) Heap Blocks: exact=11287 Buffers: shared hit=3714 read=7656 written=221 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..412.83 rows=13387 width=0) (actual time=4.901..4.901 rows=13254 loops=1) Index Cond: ((p_type)::text = 'MEDIUM PLATED NICKEL'::text) Buffers: shared read=83 -> Bitmap Heap Scan on lineitem (cost=4.72..108.72 rows=31 width=20) (actual time=0.046..0.373 rows=30 loops=13254) Recheck Cond: (l_partkey = part.p_partkey) Heap Blocks: exact=399955 Buffers: shared hit=236779 read=218250 dirtied=202 written=5220 -> Bitmap Index Scan on lineitem_l_partkey_l_quantity_l_shipmode_idx (cost=0.00..4.71 rows=31 width=0) (actual time=0.026..0.026 rows=30 loops=13254) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=40098 read=14976 written=334 -> 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=397604) Index Cond: ((o_orderkey = lineitem.l_orderkey) AND (o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=1278556 read=36924 written=1148 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=1087.809..1087.809 rows=300963 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14677kB Buffers: shared hit=110125 read=36051 written=1286 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=23.327..988.059 rows=300963 loops=1) Buffers: shared hit=110125 read=36051 written=1286 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.074..0.106 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=0.008..0.020 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.027..0.027 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=0.017..0.019 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=20.041..185.891 rows=60193 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145336 Buffers: shared hit=110123 read=36051 written=1286 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=13.000..13.000 rows=60193 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=6 read=832 written=28 -> 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=24410) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73342 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.030..0.030 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=0.005..0.011 rows=25 loops=1) Buffers: shared hit=1 Planning time: 8.223 ms Execution time: 11762.602 ms (70 rows) COMMIT; COMMIT