On the independence of data warehouse from databases in maintaining join views

摘要

In maintaining data warehouse views without interfering current databases, a Join Differential File (JDF) scheme is introduced. The scheme uses differential files from relevant logs of databases and join differential files by capturing the referential integrity signal between the base relations. Cost functions are formulated, that are analyzed the performance of the JDF. the Base method, and the pseudo differential method in various conditions. The algorithm is shown to be much better thanthe other two methods with the high communication speed. more screening situation, and small join differential files.