Invoke a UDR in an SPL routine

You use the CALL statement only to invoke a UDR from within an SPL program. You can use CALL to invoke both user-defined functions and user-defined procedures, as follows:

• When you invoke a user-defined function with the CALL statement, you must include a RETURNING clause and the name of the value or values that the function returns.
  The following statement invokes the equal() function:

  CALL equal (arg1, arg2) RETURNING result

  You cannot use the CALL statement to invoke a user-defined function that contains an OUT parameter.

• A RETURNING clause is never present when you invoke a user-defined procedure with the CALL statement because a procedure does not return a value.
  The following CALL statement invokes the log_compare() procedure:

  CALL log_compare (arg1, arg2)