Creates an external routine definition as a schema object in an
    Oracle Rdb database. External routine refers to both external
    functions and external procedures. A routine definition stores
    information in the database about a subprogram (a function or
    procedure) written in a 3GL language. The routine definition and
    the routine image are independent of each other, meaning one can
    exist without the other. However, to invoke an external routine,
    you need both the routine definition and routine image.

    SQL can invoke an external function from anywhere you can specify
    a value expression. External procedures are invoked using the
    CALL Compound_Statement.