BEGIN; BEGIN EXPLAIN select c_custkey, c_name, sum(l_extendedprice * (1 - l_discount)) as revenue, c_acctbal, n_name, c_address, c_phone, c_comment from customer, orders, lineitem, nation where c_custkey = o_custkey and l_orderkey = o_orderkey and o_orderdate >= date '1993-06-01' and o_orderdate < cast(date '1993-06-01' + interval '3 month' as date) and l_returnflag = 'R' and c_nationkey = n_nationkey group by c_custkey, c_name, c_acctbal, c_phone, n_name, c_address, c_comment order by revenue desc LIMIT 20; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Limit (cost=10260635.77..10260635.82 rows=20 width=175) -> Sort (cost=10260635.77..10264730.95 rows=1638073 width=175) Sort Key: (sum((sum((lineitem.l_extendedprice * ('1'::double precision - lineitem.l_discount)))))) DESC -> HashAggregate (cost=10200666.51..10217047.24 rows=1638073 width=175) Group Key: customer.c_custkey, customer.c_name, customer.c_acctbal, customer.c_phone, nation.n_name, customer.c_address, customer.c_comment -> Remote Subquery Scan on all (datanode_1_1,datanode_2_1,datanode_3_1,datanode_4_1,datanode_5_1,datanode_6_1,datanode_7_1,datanode_8_1) (cost=1134395.09..10159714.68 rows=1638073 width=175) -> HashAggregate (cost=1134395.09..10159714.68 rows=1638073 width=175) Group Key: customer.c_custkey, customer.c_name, customer.c_acctbal, customer.c_phone, nation.n_name, customer.c_address, customer.c_comment -> Hash Join (cost=1134395.09..10159714.68 rows=1638073 width=175) Hash Cond: (customer.c_nationkey = nation.n_nationkey) -> Nested Loop (cost=1134393.53..10137189.62 rows=1638073 width=153) -> Hash Join (cost=1134393.41..4259222.06 rows=1662934 width=149) Hash Cond: (orders.o_custkey = customer.c_custkey) -> Bitmap Heap Scan on orders (cost=121856.41..2740886.16 rows=5742850 width=8) Recheck Cond: ((o_orderdate >= '1993-06-01'::date) AND (o_orderdate < '1993-09-01'::date)) -> Bitmap Index Scan on orders_o_orderdate_o_orderkey_idx (cost=0.00..120420.70 rows=5742850 width=0) Index Cond: ((o_orderdate >= '1993-06-01'::date) AND (o_orderdate < '1993-09-01'::date)) -> Hash (cost=502771.00..502771.00 rows=15000000 width=145) -> Seq Scan on customer (cost=0.00..502771.00 rows=15000000 width=145) -> Index Scan using lineitem_l_orderkey_idx_l_returnflag on lineitem (cost=0.12..3.52 rows=1 width=12) Index Cond: (l_orderkey = orders.o_orderkey) -> Hash (cost=1.25..1.25 rows=25 width=30) -> Seq Scan on nation (cost=0.00..1.25 rows=25 width=30) (23 rows) COMMIT; COMMIT