Query Optimization Strategy for Dirty Database

With the development of the era of data,more and more dirty data exist in the database. Dirty data bring negative impact on the data and reduce the usability and efficiency of database management systems. Entity-based relational data model is one of effective data model for dirty data,in which one tuple represents an entity in real-world. With the consideration that the execution of a query operation baced on the model such as selection or connection may generate a large set of intermediate results can be useless to the final results. If these useless intermediate results are filtered in time,query efficiency can be improved. It is a crucial difference between query optimization for dirty database and that for traditional relational database. This paper focuses on the research in the process of query optimization which considers the intermediate results filtering and experiments to demonstrate.