扩展和定制基本产品数据对象方法研究

在分析扩展和定制 PDM的特定需求的基础上 ,提出了两种扩展和定制 PDM数据对象的方法 ,从适用场合和实现方法两个方面对两种方法进行了比较

Research on Extending and Customizing Fundamental Product Data Object

We discuss two main kinds of data expanding method, which meets different requirements, in detail. These methods are: (1) extending object classusing the concept of object class inheritance, we can derive sub class from the parent class. By adding new attributes and registering more message processing methods to an existing class, the function of the PDM product data can be strengthened; (2) customizing object typewith the aid of projection and joining on the basis of the fundamental table in RDBMS, we can get the sub types database views from the primary object types. Two kins of projection methods—vertical projection and horizontal projectioncan be adopted according to different needs. Two specific kinds of joining ——self joining and outer joining ——are also discussed. Adopting the above principle, the authors have successfully achieved the extending and customizing the product data object in a preliminary PDM prototype —863/CIMS Xi'an Aircraft Corporation Automatic Part List Management System.