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 = 'SMALL BRUSHED COPPER' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2154564.26..2154566.09 rows=732 width=38) (actual time=70043.129..70043.129 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=719822 read=284453 dirtied=1781 written=73 -> HashAggregate (cost=2154516.63..2154529.44 rows=732 width=38) (actual time=70043.039..70043.041 rows=2 loops=1) Buffers: shared hit=719819 read=284453 dirtied=1781 written=73 -> Nested Loop (cost=500691.17..2154034.33 rows=24115 width=38) (actual time=39967.265..69910.356 rows=24408 loops=1) Buffers: shared hit=719819 read=284453 dirtied=1781 written=73 -> Nested Loop (cost=500691.17..2147156.73 rows=24115 width=16) (actual time=39967.190..67971.434 rows=24408 loops=1) Buffers: shared hit=671003 read=284453 dirtied=1781 written=73 -> Hash Join (cost=500691.17..2140133.22 rows=24119 width=16) (actual time=39962.967..66140.466 rows=24408 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=597650 read=284453 dirtied=1781 written=73 -> Nested Loop (cost=0.00..1637216.58 rows=396855 width=16) (actual time=1.072..24403.709 rows=398500 loops=1) Buffers: shared hit=258451 read=209118 dirtied=1781 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..45725.56 rows=13127 width=4) (actual time=0.930..1026.544 rows=13250 loops=1) Index Cond: (p_type = 'SMALL BRUSHED COPPER'::text) Heap Fetches: 13250 Buffers: shared hit=21 read=11370 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.93 rows=31 width=20) (actual time=0.200..1.743 rows=30 loops=13250) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=258430 read=197748 dirtied=1781 -> Hash (cost=489204.63..489204.63 rows=918923 width=8) (actual time=39960.919..39960.919 rows=913850 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35698kB Buffers: shared hit=339196 read=75335 written=73 -> Hash Join (cost=138571.39..489204.63 rows=918923 width=8) (actual time=11978.728..39265.074 rows=913850 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=339196 read=75335 written=73 -> Bitmap Heap Scan on orders (cost=99540.77..423754.98 rows=4594614 width=12) (actual time=4947.637..17702.233 rows=4561656 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=229126 read=39228 written=36 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..98392.12 rows=4594614 width=0) (actual time=4809.618..4809.618 rows=4593594 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=17 read=13042 written=5 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=7030.804..7030.804 rows=300963 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10581kB Buffers: shared hit=110070 read=36107 written=37 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=52.739..6709.340 rows=300963 loops=1) Buffers: shared hit=110070 read=36107 written=37 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.043..0.105 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..0.018 rows=25 loops=1) Buffers: shared hit=1 -> Hash (cost=1.06..1.06 rows=1 width=4) (actual time=0.019..0.019 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=0.016..0.017 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=44.977..1320.212 rows=60193 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=110068 read=36107 written=37 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=34.217..34.217 rows=60193 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=6 read=833 written=2 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.071..0.071 rows=1 loops=24408) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73353 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.073..0.074 rows=1 loops=24408) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48816 Total runtime: 70069.103 ms (64 rows) COMMIT; COMMIT