BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select o_year, sum(case when nation = 'EGYPT' 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 = 'MIDDLE EAST' and s_nationkey = n2.n_nationkey and o_orderdate between date '1995-01-01' and date '1996-12-31' and p_type = 'STANDARD PLATED STEEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2140848.37..2140850.19 rows=729 width=38) (actual time=12944.777..12944.778 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=814546 read=183843 -> HashAggregate (cost=2140800.95..2140813.70 rows=729 width=38) (actual time=12944.717..12944.718 rows=2 loops=1) Buffers: shared hit=814543 read=183843 -> Nested Loop (cost=494549.32..2140326.51 rows=23722 width=38) (actual time=9037.362..12913.351 rows=24262 loops=1) Buffers: shared hit=814543 read=183843 -> Nested Loop (cost=494549.32..2133560.99 rows=23722 width=16) (actual time=9037.317..12854.050 rows=24262 loops=1) Buffers: shared hit=766019 read=183843 -> Hash Join (cost=494549.32..2126644.03 rows=23753 width=16) (actual time=9037.265..12684.815 rows=24262 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=695516 read=181394 -> Nested Loop (cost=0.00..1629894.76 rows=392485 width=16) (actual time=0.693..2974.002 rows=398392 loops=1) Buffers: shared hit=310072 read=154701 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..45565.10 rows=13073 width=4) (actual time=0.620..126.714 rows=13251 loops=1) Index Cond: (p_type = 'STANDARD PLATED STEEL'::text) Heap Fetches: 13251 Buffers: shared hit=1 read=11406 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.88 rows=31 width=20) (actual time=0.022..0.206 rows=30 loops=13251) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=310071 read=143295 -> Hash (cost=483190.61..483190.61 rows=908697 width=8) (actual time=9035.672..9035.672 rows=911520 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35607kB Buffers: shared hit=385441 read=26693 -> Hash Join (cost=135391.26..483190.61 rows=908697 width=8) (actual time=1772.139..8750.898 rows=911520 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=385441 read=26693 -> Bitmap Heap Scan on orders (cost=96360.64..418034.94 rows=4543487 width=12) (actual time=1209.296..3437.713 rows=4561961 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=240117 read=25861 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..95224.77 rows=4543487 width=0) (actual time=1128.171..1128.171 rows=4561961 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared read=12456 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=562.604..562.604 rows=299838 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10542kB Buffers: shared hit=145324 read=832 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=33.712..490.352 rows=299838 loops=1) Buffers: shared hit=145324 read=832 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.026..0.101 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=0.005..0.026 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..0.009 rows=1 loops=1) Filter: (r_name = 'MIDDLE EAST'::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=19.853..87.580 rows=59968 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=145322 read=832 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=13.838..13.838 rows=59968 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=5 read=832 -> Index Scan using pk_supplier on supplier (cost=0.00..0.28 rows=1 width=8) (actual time=0.006..0.006 rows=1 loops=24262) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=70503 read=2449 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.001..0.001 rows=1 loops=24262) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48524 Total runtime: 12953.328 ms (64 rows) COMMIT; COMMIT