A Logical Model for Multiversion Data Warehouses

Data warehouse systems integrate data from heterogeneous sources. These sources are autonomous in nature and change independently of a data warehouse. Owing to changes in data sources, the content and the schema of a data warehouse may need to be changed for accurate decision making. Slowly changing dimensions and temporal data warehouses are the available solutions to manage changes in the content of the data warehouse. Multiversion data warehouses are capable of managing changes in the content and the structure simultaneously however, they are relatively complex and not easy to implement. In this paper, we present a logical model of a multiversion data warehouse which is capable of handling schema changes independently of changes in the content. We also introduce a new hybrid table version approach to implement the multiversion data warehouse.