BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'MOZAMBIQUE' 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 = 'ECONOMY ANODIZED COPPER' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2186445.99..2186447.82 rows=732 width=38) (actual time=65254.375..65254.375 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=778092 read=244097 dirtied=1177 -> HashAggregate (cost=2186398.35..2186411.16 rows=732 width=38) (actual time=65254.306..65254.307 rows=2 loops=1) Buffers: shared hit=778089 read=244097 dirtied=1177 -> Nested Loop (cost=499620.02..2185905.29 rows=24653 width=38) (actual time=33804.516..65113.302 rows=25124 loops=1) Buffers: shared hit=778089 read=244097 dirtied=1177 -> Nested Loop (cost=499620.02..2178874.25 rows=24653 width=16) (actual time=33804.436..63020.559 rows=25124 loops=1) Buffers: shared hit=727841 read=244097 dirtied=1177 -> Hash Join (cost=499620.02..2171694.07 rows=24657 width=16) (actual time=33804.386..60844.988 rows=25124 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=652332 read=244097 dirtied=1177 -> Nested Loop (cost=0.00..1669798.95 rows=405705 width=16) (actual time=0.374..25445.226 rows=411320 loops=1) Buffers: shared hit=252708 read=229666 dirtied=1177 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46642.90 rows=13433 width=4) (actual time=0.318..762.685 rows=13678 loops=1) Index Cond: (p_type = 'ECONOMY ANODIZED COPPER'::text) Heap Fetches: 13678 Buffers: shared hit=4060 read=7682 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.52 rows=31 width=20) (actual time=0.203..1.783 rows=30 loops=13678) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=248648 read=221984 dirtied=1177 -> Hash (cost=488144.91..488144.91 rows=918009 width=8) (actual time=33800.558..33800.558 rows=911900 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35622kB Buffers: shared hit=399621 read=14431 -> Hash Join (cost=137860.52..488144.91 rows=918009 width=8) (actual time=5940.090..33142.158 rows=911900 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=399621 read=14431 -> Bitmap Heap Scan on orders (cost=98829.89..422721.54 rows=4590043 width=12) (actual time=3211.359..16206.101 rows=4561666 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=254783 read=13120 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..97682.38 rows=4590043 width=0) (actual time=3058.941..3058.941 rows=4589006 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=12862 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=2728.424..2728.424 rows=299493 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10530kB Buffers: shared hit=144838 read=1311 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=61.016..2469.525 rows=299493 loops=1) Buffers: shared hit=144838 read=1311 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.025..0.080 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=0.004..0.015 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: 1kB Buffers: shared hit=1 -> Seq Scan on region (cost=0.00..1.06 rows=1 width=4) (actual time=0.009..0.011 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=43.742..475.575 rows=59899 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=144836 read=1311 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=34.232..34.232 rows=59899 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=8 read=825 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.083..0.083 rows=1 loops=25124) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=75509 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.077..0.078 rows=1 loops=25124) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=50248 Total runtime: 65274.497 ms (64 rows) COMMIT; COMMIT