【摘要】 首先给出了一种面向对象的实视图模型———对象视图模型,可以在数据仓库中描述复杂对象,并有利于前端工具OLAP的实现。然后在此基础上提出了对象视图模型增量维护算法———OMVIMA,该算法能够有效地实现从数据源到数据仓库中对象(数据)的增量抽取和加载等维护工作。最后给出了算法的性能和效率分析,并通过应用实例证明了该算法比基于纯关系实视图的实现方法具有更高的效率。更多还原

【Abstract】 Proposes a kind of object-oriented materialized view model:Object-View model.Conventional relational view model of Data Warehouse(DW)cannot represent the semantics and operations of multi-dimensional data adequately,so the Object-View model is proposed.Using Object-Oriented(O-O)methodology,it can explicitly represent the semantics and reuse view(class)definitions based on the class composition hierarchies,thereby resulting in a more efficient view mechanism.Firstly,it gives the definitions of class,data type,materialized view,abstract materialized view and Object-Ori-ented data warehouse.It also presents the semantics of Object-View.Then,the incremental maintenance algorithm of Ob-ject-View is discussed in detail.Using the algorithm,it can increasingly extract and load data into warehouse efficiently.At last,it analyzes the performance and efficiency of the algorithm.The algorithm is implemented successfully in the Data Warehouse Based Justice Decision Support System.By comparison,the method of Object-View is more efficient than methods based on conventional relational view model,especially when data scale is large.更多还原