tailieunhanh - Pro BizTalk 2006 phần 7

Bạn chỉ đơn giản là có thể cập nhật tình trạng của quy tắc, các giá trị thay đổi liên quan đến sự kiện, hoặc hành động thay đổi một quy tắc hoàn toàn mà không cần phải biên dịch và triển khai lại các ứng dụng. Vì vậy, khi bạn sử dụng BRE và khi nào bạn giữ các quy tắc của bạn bên ngoài BRE? | CHAPTER 8 PLAYING BY THE RULES USE THE BUSINESS RULE ENGINE. 287 Although simple runtime rule customization can be implemented by using database tables or configuration files to store values for facts used in business rules a rule engine offers much greater flexibility than simple database tables or configuration files. A rule engine allows you to isolate the condition as well as the action from the application flow. You can simply update a rule s condition change values associated with facts or change actions in a rule altogether without the need to recompile and redeploy the application. So when do you use the BRE and when do you keep your rules outside the BRE A rule engine is suitable when your application involves significant decision making the rules are complex or change frequently the rules need to be shared across multiple applications and organizations or you are in a volatile industry sector where change is the norm or regulation is extensive and complex. Maintaining your rules in custom code that may be configured through database value lookups or configuration files is suitable when the rules are mostly static and computational or are simple even if numerous speed and throughput are more important than flexibility and maintenance cost or your business rules are never expected to change in the future eFORCE . A rule engine provides the flexibility to change not only what is being evaluated but also how when where or any other basis you can imagine. In the main application flow or logic there is no query no table and no rule-specific code. There is only a call to the rule engine passing raw data and getting back processed data. The whole logic of what to change and the basis for that change is controlled by the rule engine. Before business rule engines you were limited to the tweaking of values now you can change the way the system lets you do business Moran . What Are the Artifacts That Constitute a Business Rule In the What Is a Business Rule Engine .