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 = 'STANDARD PLATED BRASS' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2197639.52..2197641.35 rows=731 width=38) (actual time=37779.618..37779.618 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=706721 read=306881 dirtied=1197 written=90 -> HashAggregate (cost=2197591.96..2197604.75 rows=731 width=38) (actual time=37779.547..37779.549 rows=2 loops=1) Buffers: shared hit=706718 read=306881 dirtied=1197 written=90 -> Nested Loop (cost=498101.91..2197095.18 rows=24839 width=38) (actual time=27990.178..37702.062 rows=24728 loops=1) Buffers: shared hit=706718 read=306881 dirtied=1197 written=90 -> Nested Loop (cost=498101.91..2190011.10 rows=24839 width=16) (actual time=27990.092..37438.394 rows=24728 loops=1) Buffers: shared hit=657262 read=306881 dirtied=1197 written=90 -> Hash Join (cost=498101.91..2182777.91 rows=24839 width=16) (actual time=27990.044..36977.957 rows=24728 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=582928 read=306881 dirtied=1197 written=90 -> Nested Loop (cost=0.00..1682382.96 rows=408929 width=16) (actual time=0.375..7587.840 rows=406299 loops=1) Buffers: shared hit=258232 read=218004 dirtied=1197 written=86 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..47001.16 rows=13553 width=4) (actual time=0.309..331.220 rows=13533 loops=1) Index Cond: (p_type = 'STANDARD PLATED BRASS'::text) Heap Fetches: 13533 Buffers: shared hit=41 read=11622 written=2 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.36 rows=31 width=20) (actual time=0.057..0.518 rows=30 loops=13533) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=258191 read=206382 dirtied=1197 written=84 -> Hash (cost=486644.73..486644.73 rows=916575 width=8) (actual time=27988.716..27988.716 rows=911930 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35623kB Buffers: shared hit=324693 read=88877 written=4 -> Hash Join (cost=136763.03..486644.73 rows=916575 width=8) (actual time=6137.929..27202.955 rows=911930 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=324693 read=88877 written=4 -> Bitmap Heap Scan on orders (cost=97732.41..421262.57 rows=4582877 width=12) (actual time=3856.808..10221.911 rows=4561664 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=186481 read=80940 written=4 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..96586.69 rows=4582877 width=0) (actual time=3745.369..3745.369 rows=4584480 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=12634 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=2280.372..2280.372 rows=299493 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10530kB Buffers: shared hit=138212 read=7937 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=37.333..1360.930 rows=299493 loops=1) Buffers: shared hit=138212 read=7937 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.036..0.107 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=0.015..0.015 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=0.011..0.012 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=32.593..252.991 rows=59899 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=138210 read=7937 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=21.998..21.998 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=0.016..0.016 rows=1 loops=24728) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=74334 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.007..0.007 rows=1 loops=24728) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=49456 Total runtime: 37801.536 ms (64 rows) COMMIT; COMMIT