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 = 'SMALL ANODIZED NICKEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2164485.50..2164487.33 rows=729 width=38) (actual time=23850.771..23850.771 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=781830 read=226366 dirtied=3417 written=739 -> HashAggregate (cost=2164438.08..2164450.84 rows=729 width=38) (actual time=23850.712..23850.713 rows=2 loops=1) Buffers: shared hit=781827 read=226366 dirtied=3417 written=739 -> Nested Loop (cost=502335.38..2163953.54 rows=24227 width=38) (actual time=17685.327..23801.439 rows=24316 loops=1) Buffers: shared hit=781827 read=226366 dirtied=3417 written=739 -> Nested Loop (cost=502335.38..2157044.00 rows=24227 width=16) (actual time=17685.264..23689.222 rows=24316 loops=1) Buffers: shared hit=733195 read=226366 dirtied=3417 written=739 -> Hash Join (cost=502335.38..2149980.03 rows=24258 width=16) (actual time=17685.218..23431.411 rows=24316 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=660114 read=226366 dirtied=3417 written=739 -> Nested Loop (cost=0.00..1645397.89 rows=400837 width=16) (actual time=0.347..4716.671 rows=399364 loops=1) Buffers: shared hit=260223 read=210354 dirtied=3417 written=739 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..45923.20 rows=13193 width=4) (actual time=0.241..186.328 rows=13289 loops=1) Index Cond: (p_type = 'SMALL ANODIZED NICKEL'::text) Heap Fetches: 13289 Buffers: shared hit=1 read=11480 written=48 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.93 rows=31 width=20) (actual time=0.031..0.329 rows=30 loops=13289) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=260222 read=198874 dirtied=3417 written=691 -> Hash (cost=490840.54..490840.54 rows=919587 width=8) (actual time=17684.158..17684.158 rows=912000 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35625kB Buffers: shared hit=399888 read=16012 -> Hash Join (cost=138873.43..490840.54 rows=919587 width=8) (actual time=2946.718..17224.040 rows=912000 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=399888 read=16012 -> Bitmap Heap Scan on orders (cost=99842.81..425371.80 rows=4597933 width=12) (actual time=1996.876..5721.462 rows=4561702 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=255621 read=14130 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..98693.32 rows=4597933 width=0) (actual time=1894.968..1894.968 rows=4616605 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=13191 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=949.254..949.254 rows=299493 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10530kB Buffers: shared hit=144267 read=1882 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=21.013..821.502 rows=299493 loops=1) Buffers: shared hit=144267 read=1882 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.022..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=0.004..0.013 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.012..0.012 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=0.008..0.010 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=23.601..151.279 rows=59899 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=144265 read=1882 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=16.028..16.028 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=0.009..0.009 rows=1 loops=24316) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73081 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.002..0.003 rows=1 loops=24316) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48632 Total runtime: 23860.897 ms (64 rows) COMMIT; COMMIT