A System for Database Visual Querying and Query Visualization: Complementing Text and Graphics to Increase Expressiveness

In this paper we present a system intended for both visual specification of relational database queries and visual description of "ordinary" (textual) SQL queries. Through the GraphSQL visual language, SQI statements can be expressed graphically, which may be useful to help inexperienced users learn the principles at the basis of the interaction with relational databases, as well as to allow expert users to better express non-trivial queries. On the other hand, through the automatic translation functionality of our system, textual SQI statements can be turned into GraphSQI graphical representations, thus highlighting the parts of which they are composed and their interrelations.