BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'KENYA' 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 = 'AFRICA' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'STANDARD ANODIZED BRASS' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2144083.65..2144085.48 rows=731 width=38) (actual time=34555.018..34555.018 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=670668 read=333049 dirtied=4013 written=176 -> HashAggregate (cost=2144036.09..2144048.88 rows=731 width=38) (actual time=34554.931..34554.932 rows=2 loops=1) Buffers: shared hit=670665 read=333049 dirtied=4013 written=176 -> Nested Loop (cost=503892.86..2143556.05 rows=24002 width=38) (actual time=26233.877..34479.131 rows=24073 loops=1) Buffers: shared hit=670665 read=333049 dirtied=4013 written=176 -> Nested Loop (cost=503892.86..2136710.68 rows=24002 width=16) (actual time=26233.828..34278.510 rows=24073 loops=1) Buffers: shared hit=622519 read=333049 dirtied=4013 written=176 -> Hash Join (cost=503892.86..2129721.26 rows=24002 width=16) (actual time=26233.792..33851.838 rows=24073 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=550188 read=333049 dirtied=4013 written=176 -> Nested Loop (cost=0.00..1623611.59 rows=395359 width=16) (actual time=1.826..6440.697 rows=395481 loops=1) Buffers: shared hit=276410 read=190393 dirtied=3760 written=62 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..45303.63 rows=12987 width=4) (actual time=1.714..266.010 rows=13198 loops=1) Index Cond: (p_type = 'STANDARD ANODIZED BRASS'::text) Heap Fetches: 13198 Buffers: shared read=11404 written=4 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..121.22 rows=31 width=20) (actual time=0.046..0.452 rows=30 loops=13198) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=276410 read=178989 dirtied=3760 written=58 -> Hash (cost=492339.26..492339.26 rows=924288 width=8) (actual time=26230.590..26230.590 rows=911976 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35625kB Buffers: shared hit=273775 read=142656 dirtied=253 written=114 -> Hash Join (cost=139378.38..492339.26 rows=924288 width=8) (actual time=5997.872..24959.011 rows=911976 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=273775 read=142656 dirtied=253 written=114 -> Bitmap Heap Scan on orders (cost=100347.76..426735.36 rows=4621440 width=12) (actual time=3776.276..9585.668 rows=4561762 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=163727 read=106555 dirtied=253 written=114 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..99192.40 rows=4621440 width=0) (actual time=3638.616..3638.616 rows=4625776 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=360 read=12856 written=74 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=2221.257..2221.257 rows=299493 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10530kB Buffers: shared hit=110048 read=36101 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=44.156..2016.960 rows=299493 loops=1) Buffers: shared hit=110048 read=36101 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.049..0.147 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..0.034 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.022..0.022 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=0.018..0.020 rows=1 loops=1) Filter: (r_name = 'AFRICA'::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=36.985..382.419 rows=59899 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=110046 read=36101 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=24.414..24.414 rows=59899 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=7 read=826 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.015..0.016 rows=1 loops=24073) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72331 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.005..0.005 rows=1 loops=24073) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48146 Total runtime: 34571.770 ms (64 rows) COMMIT; COMMIT