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The Rule Manager classes work together to provide a central repository for business rules logic and a methodology for checking and responding to business rules in Clarion procedures. The Rule Manager classes also provide the option of visual indicators when a rule has been broken and conditional hiding or disabling of controls in the presence of broken rules.

**Why Use RuleManager?**

A primary requirement of a database system is the validation of data, or, more generally, enforcement of business rules. A common methodology is to put all validation code in the update procedure. However, the same tables may be handled by multiple procedures, //e.g.//, manual input and batch processes, and individual columns may also be updated by procedures primarily concerned with other tables.

The result is that code for validating a particular column is repeated in multiple places throughout the application, providing opportunities for inconsistency and, as the system grows, creating a maintenance nightmare.

The Rule Manager Classes and associated templates provide a mechanism for centralizing validation code so that validation, wherever it is needed, is always provided in exactly the same way by code which can be maintained in a single, central location.

In addition, the Rule Manager Classes provide facilities for identifying broken rules in a convenient manner and enforcing rules through selective disabling or hiding of controls.