Program:  Superbase 4
         Version:  1.3
         Topic:    Assigning a unique serial number to a record in a
                   file.
         Date:     August 19, 1992

         Summary:  The SER function assigns a unique serial number to
         each record in a file.  A serial number can be added to the file
         definition when a file is created or after a file contains
         records.  This technote explains how to add a field that
         generates a unique serial number to a new file and to a file
         with existing records.

         How Superbase generates the number
         The SER function generates number based on the number of records
         added to a file.  When you create the first record in a file,
         the serial number generated is one.  This value is incremented
         by one for each record you add to the file.  If records are
         deleted the serial number is never reissued.

         Create the serial number field
         1. In the File Definition dialog (choose Modify from the File
            menu), add a numeric field called Sernum.  The format should
            be able to accommodate the maximum number of records your
            file will hold.

         2. To generate the serial number automatically, make the Sernum
            field a constant.  The constant formula is SER("filename").

         3. Save the file modification.

         All new records are assigned a serial number in the Sernum
         field.

         Put serial number values in existing records
         To add a serial number field to a file that already contains
         records, follow steps one through three above, then update the
         existing records.

         1. Initialize a counter in the Database Command dialog by
            typing

            x% = 0

            Click OK. (To access the Database Command dialog, press Alt-
            F1 or select Command from the DML menu.)

         2. Select Update from the Process menu.

         3. To update all records, leave the Update Filter dialog empty
            and click OK.

         4. To add an incremental number to each record, the Update
            Definition is

            x% = x% + 1: Sernum = x%

         After this update, all records in the database have a unique
         value in the Sernum field, and all new records will be assigned
         a new number.