BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'UNITED KINGDOM' 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 = 'EUROPE' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'PROMO BURNISHED STEEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2226226.48..2226228.30 rows=731 width=38) (actual time=28219.320..28219.320 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=778798 read=220454 dirtied=1104 written=513 -> HashAggregate (cost=2226178.91..2226191.70 rows=731 width=38) (actual time=28219.257..28219.259 rows=2 loops=1) Buffers: shared hit=778795 read=220454 dirtied=1104 written=513 -> Nested Loop (cost=497993.26..2225672.61 rows=25315 width=38) (actual time=20935.558..28161.071 rows=24255 loops=1) Buffers: shared hit=778795 read=220454 dirtied=1104 written=513 -> Nested Loop (cost=497993.26..2218452.77 rows=25315 width=16) (actual time=20935.495..28013.214 rows=24255 loops=1) Buffers: shared hit=730285 read=220454 dirtied=1104 written=513 -> Hash Join (cost=497993.26..2211080.97 rows=25315 width=16) (actual time=20935.453..27709.729 rows=24255 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=657393 read=220454 dirtied=1104 written=513 -> Nested Loop (cost=0.00..1710749.62 rows=416989 width=16) (actual time=0.401..5531.690 rows=395984 loops=1) Buffers: shared hit=264991 read=199255 dirtied=1104 written=513 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..47790.19 rows=13820 width=4) (actual time=0.310..226.212 rows=13188 loops=1) Index Cond: (p_type = 'PROMO BURNISHED STEEL'::text) Heap Fetches: 13188 Buffers: shared read=11396 written=36 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.02 rows=31 width=20) (actual time=0.038..0.388 rows=30 loops=13188) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=264991 read=187859 dirtied=1104 written=477 -> Hash (cost=486542.08..486542.08 rows=916094 width=8) (actual time=20933.665..20933.665 rows=913799 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35696kB Buffers: shared hit=392399 read=21199 -> Hash Join (cost=136710.35..486542.08 rows=916094 width=8) (actual time=4422.110..19704.467 rows=913799 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=392399 read=21199 -> Bitmap Heap Scan on orders (cost=97679.73..421173.76 rows=4580469 width=12) (actual time=2995.225..6726.536 rows=4561664 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=261097 read=6324 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..96534.61 rows=4580469 width=0) (actual time=2832.571..2832.571 rows=4584480 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=6310 read=6324 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=1426.585..1426.585 rows=300963 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10581kB Buffers: shared hit=131302 read=14875 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=33.017..1240.143 rows=300963 loops=1) Buffers: shared hit=131302 read=14875 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.039..0.099 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..0.024 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=0.012..0.013 rows=1 loops=1) Filter: (r_name = 'EUROPE'::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=29.049..232.283 rows=60193 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=131300 read=14875 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=19.364..19.364 rows=60193 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=6 read=833 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.010..0.011 rows=1 loops=24255) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=72892 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.003..0.004 rows=1 loops=24255) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48510 Total runtime: 28233.934 ms (64 rows) COMMIT; COMMIT