Integrating Web and database information for collaboration through explicit metadata

Loosely structured Web-based collections and more highly structured database resources have value to the extent that they convey meaning, understanding, and usable information. Metadata, or `data about data´ is the means of conveying this meaning, and thus it is an essential ingredient for successful collaboration involving diverse and distributed information. We characterize three dimensions of metadata and then develop a unified metadata representation that spans heterogeneous database systems. Our ubiquitous representation also incorporates structured documents and Web-based information. This is in contrast with the current approach of having a different metadata representation for each data model, such as relational, object-oriented, etc. Our extensible representation also supports knowledge-based representation of semantics. We believe this approach will substantially enhance collaboration over diverse information resources