Querying Nested Historical Relations in Heterogeneous Databases Environment

We study schema integration problems for consolidating historical information from nested relational databases in heterogeneous databases environment. These nested relations are for supporting complex objects. In heterogeneous databases systems, probabilistic partial values have been used to resolve some schema integration problems. In this paper, we extend the concept of probabilistic partial values in database relations to the nested historical relations in heterogeneous databases environment. Our study combines the research in nested relational databases, temporal databases, and corporate data warehousing for database applications. We develop a full set of temporal relational operators over nested historical relational data model.