Programmer Utilities › Introduction › Overview › Debug Aids › Utility to Copy a List of Database Files › Techniques for Preparing Test Data

Techniques for Preparing Test Data

The snapshot technique can be used to complement two other techniques of preparing test data on the i OS:

• Use of test pack libraries: you will probably keep one or more data libraries, each containing a complete set of all of the application files required by a system: these alternative libraries can be used in place of the library of live files when testing. Such a library will typically contain the physical files and all necessary dependent logical views. Creating or restoring such a library may be fairly cumbersome and slow, as it must either be done via an off-line media, or by using the i OS command Create Duplicate Object (CRTDUPOBJ) in a controlled manner that is on physical files before logical files.
• Use of journalling. Journalling may be of use of the immediate unravelling or tracing of errors. It is of limited use if there has been significant subsequent update of the database.

The Toolkit utility Copy File simplifies the process of creating test data: you need to keep only one or two complete sets of test files. Repeated snapshots can be taken of the contents of selected physical files: you can specify which files by use of the Toolkit facilities Create List and Edit List. The snapshots constitute a full description of the data in the library for the purposes of recovery.

The files within each snapshot can be given an identifying prefix. This allows you to store many snapshots of a given file in the same library.