V: A Visual Query Language for Multimodal Interfaces

This thesis proposes a two-dimensional, visual, direct manipulation query language intended to be used as an alternate modality to natural language in a multimodal interface. The language focuses on the visualisation of the logic of queries, and is intended to be flexible, extensible, and to have at least the expressive power of first order predicate logic with constraints. The language provides a basis for future inclusion of higher order logic (and thus a framework for database navigation with the language itself), DBMS features, and generalised quantifiers. As far as we have been able to judge, no such visual language of equal expressive power already exists. A "proof of concept" prototype has been implemented that illustrates some of the key concepts of the language