Querying Faceted Databases

Faceted classification allows one to model applications with complex classification hierarchies using orthogonal dimensions. Recent work has examined the use of faceted classification for browsing and search. In this paper, we go further by developing a general query language, called the entity algebra, for hierarchically classified data. The entity algebra is compositional, with query inputs and outputs being sets of entities. Our language has linear data complexity in terms of space and quadratic data complexity in terms of time. We compare the entity algebra with the relational algebra in terms of expressiveness. We also describe an implementation of the language in the context of two application domains, one for an archeological database, and another for a human anatomy database. ∗ This research was supported by NSF grant IIS-0121239. 0 

• Type: Conference
• Year: 2004
• Where: SEMWEB
• Authors: Kenneth A. Ross, Angel Janevski
• Keywords: Data Complexity, Entity Algebra, Faceted Classification, SEMWEB 2004