WS-QBE: A QBE-Like Query Language for Complex Multimedia Queries

The visual database query language QBE (query by example) is a classical, declarative query language based on the relational domain calculus. However, due to insufficient support of vagueness QBE is not an appropriate query language for formulating similarity queries required in the context of multimedia databases. In this work we propose the query language WS-QBE which combines a schema to weight query terms as well as concepts from fuzzy logic and QBE into one language. WS-QBE enables a visual, declarative formulation of complex similarity queries. The semantics of WS-QBE is defined by a mapping of WS-QBE queries onto the similarity domain calculus SDC which is proposed here, too.