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 = 'SMALL PLATED TIN' ) as all_nations group by o_year order by o_year; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1725119.33..1725121.16 rows=730 width=38) (actual time=11598.304..11598.305 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=1978668 read=315259 dirtied=1699 written=97 -> HashAggregate (cost=1725071.84..1725084.62 rows=730 width=38) (actual time=11598.241..11598.241 rows=2 loops=1) Group Key: date_part('year'::text, (orders.o_orderdate)::timestamp without time zone) Buffers: shared hit=1978665 read=315259 dirtied=1699 written=97 -> Hash Join (cost=39444.73..1724586.00 rows=24292 width=38) (actual time=1190.606..11560.173 rows=24416 loops=1) Hash Cond: (supplier.s_nationkey = n2.n_nationkey) Buffers: shared hit=1978665 read=315259 dirtied=1699 written=97 -> Nested Loop (cost=39443.17..1724128.96 rows=24292 width=16) (actual time=1190.533..11526.611 rows=24416 loops=1) Buffers: shared hit=1978661 read=315259 dirtied=1699 written=97 -> Hash Join (cost=39442.88..1716282.79 rows=24317 width=16) (actual time=1190.504..11330.258 rows=24416 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=1905271 read=315259 dirtied=1699 written=97 -> Nested Loop (cost=412.19..1676552.99 rows=121585 width=20) (actual time=6.993..10075.144 rows=121754 loops=1) Buffers: shared hit=1795139 read=279154 dirtied=1699 written=95 -> Nested Loop (cost=411.76..1480067.13 rows=401273 width=16) (actual time=6.854..4132.373 rows=400552 loops=1) Buffers: shared hit=274985 read=195032 dirtied=1460 written=73 -> Bitmap Heap Scan on part (cost=411.19..28030.66 rows=13260 width=4) (actual time=6.787..149.225 rows=13365 loops=1) Recheck Cond: ((p_type)::text = 'SMALL PLATED TIN'::text) Heap Blocks: exact=11430 Buffers: shared hit=4007 read=7492 written=5 -> Bitmap Index Scan on part_p_type_p_partkey_idx (cost=0.00..407.88 rows=13260 width=0) (actual time=4.447..4.447 rows=13365 loops=1) Index Cond: ((p_type)::text = 'SMALL PLATED TIN'::text) Buffers: shared read=69 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.56..109.20 rows=31 width=20) (actual time=0.029..0.288 rows=30 loops=13365) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=270978 read=187540 dirtied=1460 written=68 -> Index Scan using pk_orders on orders (cost=0.43..0.48 rows=1 width=12) (actual time=0.014..0.014 rows=0 loops=400552) 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=1520154 read=84122 dirtied=239 written=22 -> Hash (cost=35280.69..35280.69 rows=300000 width=4) (actual time=1181.071..1181.071 rows=300270 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 14653kB Buffers: shared hit=110132 read=36105 written=2 -> Nested Loop (cost=906.18..35280.69 rows=300000 width=4) (actual time=21.675..1088.777 rows=300270 loops=1) Buffers: shared hit=110132 read=36105 written=2 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.049..0.077 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..0.015 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.018..0.018 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=0.011..0.012 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=18.907..206.494 rows=60054 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Heap Blocks: exact=145400 Buffers: shared hit=110130 read=36105 written=2 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.11 rows=60000 width=0) (actual time=12.346..12.346 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=0.007..0.007 rows=1 loops=24416) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73390 -> Hash (cost=1.25..1.25 rows=25 width=30) (actual time=0.023..0.023 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: 8.508 ms Execution time: 11599.100 ms (68 rows) COMMIT; COMMIT