Alias

     (database) The name of a work area; an alternate name given to a
     database file.  Aliases are often used to give database files
     descriptive names and are assigned when the database file is opened.  If
     no alias is specified when the database file is USEd, the name of the
     database file becomes the alias.

     An alias can be used to reference both fields and expressions (including
     user-defined functions).  In order to alias an expression, the
     expression must be enclosed in parentheses.