HP Integrity NonStop J-Series - Manual (Page 140)

TAILORING AN APPLICATION
Defining the Operations That an Application Can Perform
DEFINING THE OPERATIONS THAT AN APPLICATION CAN PERFORM
A basic ENABLE application can perform delete, insert, read, or
update operations on the data base files to which it has access.
Depending on the purpose for which you are generating the
application, you might want either to limit or to enhance these
operations for a particular application.
To determine the kind of operations that you want to allow, ask
yourself the following questions about each box used by the
application:
• Is the purpose of the application to display information in
this box? If so, consider limiting the application to read-
only operations for the box.
• Will a user of the application need to delete or update
existing records in the box? If not, consider limiting the
application to read and insert operations only for the box.
• Is the box a child box? If so, consider providing the
application with the ability to perform an automatic read
operation for the box. Although providing this ability might
slow processing time slightly, it greatly enhances the
usability of the application since the user does not have to
press a function key to request the read operation.
Define the operations that an application can perform by
supplying values for the ABILITY (or file operation) attributes.
These attributes are: DELETE, FILL, INSERT, READ, and UPDATE.
Limiting the Operations an Application Can Perform
To limit the operations that an application can perform on a
particular file, supply OFF as a value for the appropriate
ABILITY attribute when you describe the box that represents the
file. Consider, for example, the "employee-info" application
described earlier in this section. Since the purpose of this
application is to display information about employees and their
dependents, "employee-info" only requires read access to the
"employee" and "depend" files. You can restrict the application
to read-only operations by using the following SET command before
you add "employ-box" and "depends-box":
SET BOX DELETE OFF, INSERT OFF, UPDATE OFF
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