Metadata management for federated databases
CARLOS R. ORDÓÑEZ, Zhibo Chen, Javier Garcı́a-Garcı́a · 2007
A federated database consists of several loosely integrated databases, where each database may contain hundreds of tables and thousands of columns, interrelated by complex foreign key relationships. In general, there exists a lot of semistructured data elements outside the database repre-sented by documents ( les), created and updated by mul-tiple users and programs. Documents have references to multiple databases and subsets of their tables and columns. Manually tracking which specic tables and columns are re-ferred to by a document, accessed by a specic program or user is a daunting task. With such a goal in mind, we present a system that builds metadata models for a feder-ated database using a relational database as a central ob-ject type and metadata repository. Metadata includes table and columns coming from logical data models corresponding to each database, as well as documents representing exter-nal semistructured data sources. SQL statements assemble metadata and data types to create objects and relationships as relational tables for easy querying. We discuss potential applications in federated scientic databases. 1.