Research And Design Of The OLAP Assistant Tools Based On Relational Database

OLAP is one kind of multi-dimension analytic technology, which recently arises with extensive application in data warehouse, of which ROLAP is one of the most commonly used patterns. Most of OLAP product now in market is based on the pattern. A lot of problems could be involved to carry out ROLAP, and the quality of bottom date should be the key factor. Nowadays, the companies accumulate quantity of data recourses, which, however, usually appear as geographic distribution, managerial autonomy, scheme isomery and should be given pre-clean and standardization to supply high quality data for ROLAP engine. Though related tools are offered by fashioned OLAP, they are all directed towards special data source which causes application limitation and high price.The purpose of this paper is to offer extension interface downwardly for different data sources to expand processing ability of isomeric data sources;to give midst data clean and standardization;to present visualized multi-dimension data analyzed by OLAP engine to client-side with compatibility with the main ROLAP engine product.Firstly, a frame construction of ROLAP assistant tools based on XML and metadata after detailed analysis of ROLAP principle, metadata theory and general design methods of ETL toos. In this frame construction, the metadata is adopted as core and XML is used as descript language which is stored in special DTD pattern in element data warehouse. The SAX and DOM can be used to analyze data documents with DTD pattern to get element data needed. The frame construction mentioned above can make it convenient for development personnel to expand and adopt element data warehouse to male them more focused in design of element data and pattern related tools need.Secondly, based the above frame construction, the design and realization of two tools including ETL assistant tool and multi-dimension visualization tool are presented. Consideringproblems of product in customer concurrent control such as efficiency and performance, a design scheme of data warehouse link tank is presented using multi-thread technology, which realizes high efficient data warehouse dynamic link and control.Finally, related tests are made on above tools based on SQL Server 2000 data warehouse and MS Analysis Services. The result shows that it is advisable to use the given frame construction and multi-dimension visualization tool also realizes the well interaction between multi-dimension data visualized indication and customers.