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 = 'MEDIUM ANODIZED NICKEL' ) as all_nations group by o_year order by o_year; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=2192049.23..2192051.06 rows=731 width=38) (actual time=25908.194..25908.195 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=771431 read=232354 dirtied=2921 written=4735 -> HashAggregate (cost=2192001.66..2192014.46 rows=731 width=38) (actual time=25908.107..25908.110 rows=2 loops=1) Buffers: shared hit=771428 read=232354 dirtied=2921 written=4735 -> Nested Loop (cost=502520.74..2191506.08 rows=24779 width=38) (actual time=19038.123..25851.541 rows=24363 loops=1) Buffers: shared hit=771428 read=232354 dirtied=2921 written=4735 -> Nested Loop (cost=502520.74..2184439.11 rows=24779 width=16) (actual time=19038.044..25710.965 rows=24363 loops=1) Buffers: shared hit=722702 read=232354 dirtied=2921 written=4735 -> Hash Join (cost=502520.74..2177223.42 rows=24779 width=16) (actual time=19037.997..25411.670 rows=24363 loops=1) Hash Cond: (lineitem.l_orderkey = orders.o_orderkey) Buffers: shared hit=649503 read=232354 dirtied=2921 written=4735 -> Nested Loop (cost=0.00..1672414.13 rows=408153 width=16) (actual time=0.551..5353.914 rows=395899 loops=1) Buffers: shared hit=247727 read=218485 dirtied=2668 written=221 -> Index Only Scan using part_p_type_p_partkey_idx on part (cost=0.00..46683.67 rows=13447 width=4) (actual time=0.453..212.732 rows=13184 loops=1) Index Cond: (p_type = 'MEDIUM ANODIZED NICKEL'::text) Heap Fetches: 13184 Buffers: shared hit=1 read=11314 written=20 -> Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem (cost=0.00..120.59 rows=31 width=20) (actual time=0.037..0.377 rows=30 loops=13184) Index Cond: (l_partkey = part.p_partkey) Buffers: shared hit=247726 read=207171 dirtied=2668 written=201 -> Hash (cost=491001.26..491001.26 rows=921559 width=8) (actual time=19036.193..19036.193 rows=911362 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 35601kB Buffers: shared hit=401773 read=13869 dirtied=253 written=4514 -> Hash Join (cost=139082.51..491001.26 rows=921559 width=8) (actual time=4267.445..18532.790 rows=911362 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=401773 read=13869 dirtied=253 written=4514 -> Bitmap Heap Scan on orders (cost=100051.89..425475.81 rows=4607795 width=12) (actual time=2948.736..6888.743 rows=4561761 loops=1) Recheck Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=256460 read=13026 dirtied=253 written=4293 -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..98899.94 rows=4607795 width=0) (actual time=2855.289..2855.289 rows=4612043 loops=1) Index Cond: ((o_orderdate >= '1995-01-01'::date) AND (o_orderdate <= '1996-12-31'::date)) Buffers: shared hit=773 read=12406 written=4206 -> Hash (cost=35280.62..35280.62 rows=300000 width=4) (actual time=1318.269..1318.269 rows=299838 loops=1) Buckets: 32768 Batches: 1 Memory Usage: 10542kB Buffers: shared hit=145313 read=843 written=221 -> Nested Loop (cost=906.17..35280.62 rows=300000 width=4) (actual time=33.423..1146.238 rows=299838 loops=1) Buffers: shared hit=145313 read=843 written=221 -> Hash Join (cost=1.07..2.47 rows=5 width=4) (actual time=0.040..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=0.006..0.019 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=0.015..0.016 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=30.606..209.264 rows=59968 loops=5) Recheck Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=145311 read=843 written=221 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_idx (cost=0.00..890.09 rows=60000 width=0) (actual time=21.622..21.622 rows=59968 loops=5) Index Cond: (c_nationkey = n1.n_nationkey) Buffers: shared hit=6 read=831 written=219 -> 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=24363) Index Cond: (s_suppkey = lineitem.l_suppkey) Buffers: shared hit=73199 -> Index Scan using pk_nation on nation n2 (cost=0.00..0.27 rows=1 width=30) (actual time=0.003..0.003 rows=1 loops=24363) Index Cond: (n_nationkey = supplier.s_nationkey) Buffers: shared hit=48726 Total runtime: 25917.791 ms (64 rows) COMMIT; COMMIT