BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'JAPAN' 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 PLATED BRASS' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1763066.34..1763068.17 rows=732 width=38) (actual time=7020.166..7020.167 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=1808217 read=211241 -> HashAggregate (cost=1763018.70..1763031.51 rows=732 width=38) (actual time=7020.104..7020.106 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1808214 read=211241 -> Hash Join (cost=39455.68..1762520.64 rows=24903 width=38) (actual time=612.796..6986.216 rows=24355 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1808214 read=211241 -> Nested Loop (cost=39454.12..1762052.14 rows=24903 width=16) (actual time=612.721..6956.651 rows=24355 loops=1) Buffers: shared hit=1808210 read=211241 -> Hash Join (cost=39453.82..1754016.85 rows=24903 width=16) (actual time=612.668..6784.450 rows=24355 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1737467 read=208793 -> Nested Loop (cost=423.14..1714270.22 rows=124513 width=20) (actual time=7.129..6115.962 rows=122363 loops=1) Buffers: shared hit=1592060 read=207963 -> Nested Loop (cost=422.70..1513760.15 rows=409510 width=16) (actual time=7.046..3118.452 rows=402271 loops=1) Buffers: shared hit=309395 read=160037 -> Bitmap Heap Scan on part (cost=422.14..28494.08 rows=13640 width=4) (actual time=6.983..148.466 rows=13402 loops=1) Recheck Cond: ((p_type)::text = 'MEDIUM PLATED BRASS'::text) Heap Blocks: exact=11459 Buffers: shared hit=9 read=11519 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..418.73 rows=13640 width=0) (actual time=4.600..4.600 rows=13402 loops=1) Index Cond: ((p_type)::text = 'MEDIUM PLATED BRASS'::text) Buffers: shared read=69 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..108.58 rows=31 width=20) (actual time=0.021..0.212 rows=30 loops=13402) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=309386 read=148518 -> Index Scan using orders_o_orderkey_o_orderdate_idx on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.007..0.007 rows=0 loops=402271) Index Cond: ((o_orderkey = lineitem.l_orderkey) AND (o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=1282665 read=47926 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=602.523..602.523 rows=300270 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14653kB Buffers: shared hit=145407 read=830 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=21.037..525.639 rows=300270 loops=1) Buffers: shared hit=145407 read=830 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.039..0.095 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=0.003..0.017 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 = '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=17.763..95.321 rows=60054 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145400 Buffers: shared hit=145405 read=830 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=11.822..11.822 rows=60054 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=5 read=830 -> Index Scan using pk_supplier on supplier (cost=0.29..0.31 rows=1 width=8) (actual time=0.006..0.006 rows=1 loops=24355) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=70743 read=2448 -> 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=0.003..0.008 rows=25 loops=1) Buffers: shared hit=1 Planning time: 9.243 ms Execution time: 7020.911 ms (66 rows) COMMIT; COMMIT