Another common modification to an RMSfile is to update an existing data field. In the following exercise we update the telephone field to increase its length to a size which is sufficient to contain the area code as well as the local number. Since telephone numbers in a format such as nnn/nnn-nnnn have twelve characters, thirteen characters must be allocated for this field. The extra character reserves space for the terminator character.
1. From the Data Files Menu, select choice D2 - Modify File Definition.
The system presents the Modify Data File Definition parameter screen.
Enter sub in the field for the filename, then press STORE <F5>.
2. The screen will display the File Definition form.
3. Press the SWITCH key <F7>. This appends a Field Description form to the File Definition form.
4. Press the NEXT key <F3>. The telephone field should appear.
5. To update the telephone field, press the UPDATE key <F4>. Notice that the word UPDATE appears in the lower left-hand corner of the screen. Press the Tab key twice to position the cursor at the start of the Field Length field. Enter 13 and press RETURN.
6. To store the updated description, press the STORE key <F5>.
7. Now that all the changes have been made to the RMSfile, write the modified file by pressing the EXIT key <F8>.
The program displays the following message:
Converting logical data file sub to new definition...
Conversion of sub done.
Push RETURN to return to menu....
There is a short pause while this file conversion takes place.
Push return to display the Data Files Menu.
8. Select choice L2 - List Data File Dictionary from the Data Files Menu.
On the List Data File Dictionary parameter form, specify the RMSfile sub and press STORE <F5>.
Press RETURN to redisplay the Data Files Menu.
This concludes the steps to modify the RMSfile sub by updating the telephone field.