BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'CHINA' 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 = 'ASIA' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'MEDIUM BRUSHED COPPER' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1715929.33..1715931.15 rows=729 width=38) (actual time=14408.810..14408.811 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=1691942 read=313683 dirtied=392 written=5173 -> HashAggregate (cost=1715881.91..1715894.67 rows=729 width=38) (actual time=14408.731..14408.733 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1691939 read=313683 dirtied=392 written=5173 -> Hash Join (cost=39444.32..1715401.69 rows=24011 width=38) (actual time=1703.897..14361.601 rows=24178 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1691939 read=313683 dirtied=392 written=5173 -> Nested Loop (cost=39442.76..1714949.92 rows=24011 width=16) (actual time=1703.832..14316.334 rows=24178 loops=1) Buffers: shared hit=1691935 read=313683 dirtied=392 written=5173 -> Hash Join (cost=39442.47..1707202.45 rows=24011 width=16) (actual time=1703.782..14079.759 rows=24178 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1619394 read=313555 dirtied=392 written=5172 -> Nested Loop (cost=411.78..1667481.45 rows=120054 width=20) (actual time=20.361..12254.600 rows=121278 loops=1) Buffers: shared hit=1482238 read=304474 dirtied=392 written=5172 -> Nested Loop (cost=411.35..1473335.67 rows=396512 width=16) (actual time=20.277..5938.143 rows=399212 loops=1) Buffers: shared hit=248091 read=218298 dirtied=392 written=3851 -> Bitmap Heap Scan on part (cost=410.78..27966.58 rows=13207 width=4) (actual time=20.186..94.496 rows=13305 loops=1) Recheck Cond: ((p_type)::text = 'MEDIUM BRUSHED COPPER'::text) Heap Blocks: exact=11358 Buffers: shared hit=11359 read=82 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..407.48 rows=13207 width=0) (actual time=17.341..17.341 rows=13305 loops=1) Index Cond: ((p_type)::text = 'MEDIUM BRUSHED COPPER'::text) Buffers: shared hit=1 read=82 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..109.13 rows=31 width=20) (actual time=0.036..0.428 rows=30 loops=13305) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=236732 read=218216 dirtied=392 written=3851 -> Index Scan using orders_o_orderkey_o_orderdate_idx on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.015..0.015 rows=0 loops=399212) Index Cond: ((o_orderkey = lineitem.l_orderkey) AND (o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=1234147 read=86176 written=1321 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=1677.480..1677.480 rows=300270 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14653kB Buffers: shared hit=137156 read=9081 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=36.794..1558.593 rows=300270 loops=1) Buffers: shared hit=137156 read=9081 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.064..0.113 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..0.019 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.026..0.026 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=0.019..0.020 rows=1 loops=1) Filter: (r_name = 'ASIA'::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=28.265..298.059 rows=60054 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145400 Buffers: shared hit=137154 read=9081 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=19.335..19.335 rows=60054 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=315 read=520 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.008..0.009 rows=1 loops=24178) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72541 read=128 written=1 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.024..0.024 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..0.005 rows=25 loops=1) Buffers: shared hit=1 Planning time: 9.633 ms Execution time: 14410.236 ms (66 rows) COMMIT; COMMIT