Rules Management and Automation With Common Knowledge

FAQ

Object Connections is committed to providing you with a range of online support and maintenance facilities. Support is currently provided free to all registered users who have purchased or are in the process of evaluating Common Knowledge.

Why does the licence key emailed to me not work correctly?
You may receive an evaluation or purchase licence key notification email in which the licence key has been corrupted and split across more than one line.

This can be caused by email systems that force line-breaks at a fixed line length boundary (e.g. 70 characters).

If this occurs, please forward the notification email containing the corrupted licence key to support and you will be sent an updated notification containing a valid licence key.

Note: Evaluation and purchase email notifications will always contain a single licence key. If you receive a notification containing what appears to be multiple licence keys or a licence key that spans multiple lines then you should contact support.
Why do I get an "Unknown object" error when compiling my rules?
This is a common mistake and this answer applies to use of all libraries. Although the library is in the application it may have the wrong scope. That is, perhaps the library has been included in the context of a rule extender such as a Decision Table or Script, making it inaccessible from from other rule extenders.
If this is the case then move the library from the table or script context and add it to the knowledgebase or application environment context.

Contexts are scoped so definitions such as objects and libraries that are contained in a context can only be "seen" by rule extenders at or below the level of that context. Rule extenders above or at the same level will not be able to access the definitions.

For example:
```
ApplicationEnvironment
-- Context
-- ...
-- Knowledgebase
---- Context
------ MathLib
---- DecisionTable
------ Context
-------- DateTimeLib
---- Script
------ Context
------ ... 
```
In the above example the DecisionTable and the Script could access the functions in the Math library, however only the Decision Table will have access to the functions in the DateTime library.

For example, if an expression in the Script references the Now or EncodeDate functions in the Math Library then an "Unknown object" error would result on compilation. To correct this, just change the layout of your environment as follows. By moving the library to the Application Environment or Knowledgebase context, all the functions contained in the library will be available from all rule extenders in the environment or within the knowledgebase:
```
ApplicationEnvironment
-- Context
---- DateTimeLib
---- ...
-- Knowledgebase
---- Context
------ MathLib
---- DecisionTable
------ Context
------ ...
---- Script
------ Context
------ ...
```
Why are there so many Context objects associated with an Application Environment?
Contexts allow you to limit the scope of the definitions used by elements within an Application Environment. Each major element (Environments, Knowledgebases and rule extenders) has a Context. Definitions contained within a Context can be accessed by the element owning the Context and all elements that are children of the element owning the Context. For example, all rule extenders contained within a Knowledgebase can access definitions contained in their own Context, the Context of the Knowledgebases containing the Rule Extender and the Context of the Application Environment containing the Knowledgebase. They cannot access the definitions contained in the Context of other rule extenders or other Knowledgebases.
Note: Common Knowledge Studio Version 3 introduced a mechanism for hiding empty context elements within the Workspace view. Simply click on the View Empty button to hide empty context elements.
What is the best way to view a Decision Table that has many rules but only a few conditions and actions?
The decision table editor allows you to view decision tables in a horizontal or vertical orientation. For decision tables that have many rules but only a few conditions and actions, it is better to view the decision table in a vertical orientation where the rules are displayed vertically down the left hand side of the table. This allows the available screen space to be more optimally used and makes editing and viewing the decision table much easier.

How can I evaluate my rules within Common Knowledge Studio and have it prompt me for the required input values?
Rules can be evaluated from within Common Knowledge Studio by selecting the item that you want to evaluate and pressing the F9 key. Alternatively, you can right click on the item and select the Execute menu item. To have Common Knowledge Studio prompt you for the values of the objects used by your rules, ensure that when defining those objects in the Context editor, you select the Enabled checkbox in the Prompting section. You can also specify a Prompt to be used when Common Knowledge Studio requires a value for the object.
Note: You can execute a Knowledgebase or a rule extender. Executing a Knowledgebase will cause the first rule extender in the Knowledgebase to be executed. You can reorder the rule extenders contained in a Knowledgebase from within Common Knowledge Studio if required.
Can I encrypt my Common Knowledge Studio files so they are secure?
Yes! Select the Save Options... button on the Application Environment properties dialog and check the Encryption check box. You will need to enter a password and a confirmation of that password. When your Application Environment is saved, it will be encrypted using the Blowfish Encryption algorithm. When you load your Application Environment again in Common Knowledge Studio, you will be prompted for the password.
Can I manually edit the Common Knowledge XML (.aex) files using a text editor?
Common Knowledge AEX files are text files containing your business rules definitions using XML (eXtensible Markup Language). These files can be edited manually using a text editor; however, it is not recommended, and Object Connections will only provide support for Application Environments that have been edited manually if they can be successfully opened by Common Knowledge Studio.
Can I get Common Knowledge Studio to only ask once for the value of an object when I am evaluating my rules from within Common Knowledge Studio?
Yes you can. Select the Tools|Studio Options... option from the main menu and select the Once Only checkbox in the prompting section of the Preferences tab, then press OK.
How can I more clearly display and edit a very large Decision Tree?
The Decision Tree editor allows you to view your decision trees in two modes. These are the tree view and hierarchical view. The hierarchical view is a more compact way of editing large decision trees; however, the tree view gives a more structured view of your decision trees. You can also use the zoom-in option to make more of the tree visible in both tree view and hierarchical view.
How can I re-enable the tip-of-the-day dialog?
From the menu bar select Tools|Studio Options... Check the Show Tips at Startup checkbox in the Tip Of The Day section of the Preferences tab, then press OK. Restart Common Knowledge Studio.
What is the difference between Parse and Compile?
Parsing ensures that your business rules definitions are syntactically correct. Compiling ensures that your business rules are syntactically correct and that all references to identifiers can be resolved. Your business rules must be able to be compiled before they can be evaluated.
Do I have to Compile then Execute every time I want to evaluate my rules?
No! You can just execute your rules. If your business rules have not been compiled then they will be automatically compiled before they are executed.
How can I get Common Knowledge Studio to reload the last Application Environment I was working with?
Select the Tools|Environment Options from the main menu and ensure the Studio Layout checkbox is checked. This will cause all open Environments to be automatically reloaded next time Common Knowledge Studio is run.
How do I get Common Knowledge Studio to allow me to edit Identities?
By default, identities are not shown on many properties dialogs as they are considered to be an advanced feature. To have identities displayed for all elements that have an identity, select the Tools|Studio Options from the main menu and ensure the Show Identities option in the Expert Mode section of the Preferences tab is checked.
Why does my generated HTML documentation look like some graphics are missing?
When Common Knowledge was installed, a number of directories were set up containing HTML templates and graphics used for the generated documentation. If your generated documentation appears to have missing components, check that the correct directories have been specified by selecting the Tools|Studio Options from the main menu then going to the Paths page. The Document Generation Templates directory should be set to the <INSTALLDIR>BinTemplates directory and the Document Generation Images directory should be set to <INSTALLDIR>BinTemplatesImages where <INSTALLDIR> is the directory that Common Knowledge was installed into (eg. "C:Program FilesObject ConnectionsCommon Knowledge").
Can Common Knowledge be used with .NET applications?
Yes! As of version 3.0, Common Knowledge includes a DotNET version of the rules engine API. Alternatlvely, the ActiveX Rules Engine can be used from .NET languages including VB/NET, C# and C++.NET.
How can I access Context Objects and Definitions in another Rule Extenders context?
Use a Context Path to "point" to the Rule Extender containing the Context Objects you want to access.
How can I access (execute) a Rule Extender in another Knowledgebase?
Use a Context Path to "point" to the Knowledgebase containing the Rule Extender you want to access.