Hi everybody, please share your opinions/answer regarding foll. oracle q: There are two tables, customer and order tables: Customer CustomerID CustomerName Phone Order OrderID CustomerID Orders Query: Select Customer.CustomerID, Order.OrderID, Order.Orders, Customer.CustomerName from Customer, Order where CustomerID >=1000; Which part of the query will take maximum time of execution? - prat.
Joined: Sep 28, 2001
looks like a cartesian join to me...
Joined: Apr 25, 2003
MAximum time of the query will be spent in scanning Orders table as it will be full table scan for that table. Changing where clause to " where customer.customerId >=1000 and order.customerId=customer.customerId" will avoid this full scan.