The only way to do this is to use a SQL Command that uses aliases to rename the fields that get returned from the database. For example:
SELECT EmpName as Field1, EmpEmail as Field2 FROM TblEmployee
When using this code, you can dynamically use different fields from the database, but keep the alias names the same. That way CR will always see the fields 'Field1', 'Field2', etc. coming from the database.