VISIONARY: A viewpoint-based visual language for querying relational databases

The adoption of a visual interface can simplify the query formulation proce ss in DBMSs by enabling naive users to interact with a friendly environment . In this work, we propose a visual query language based on a diagrammatic paradigm, used for both data and query representation. The external data mo del is called vision and is made up of the visual primitives of concept and association. The external query model is based on the definition of a view point, which is a perspective for accessing data defined dynamically by sel ecting a concept of primary interest. Internally, the data model is relatio nal and the query language is SQL. An intermediate graph-based model ensure s consistent mapping between the visual and the relational worlds. Our lang uage has been implemented within a tool which can be mounted on top of any relational DBMS supporting ODBC. The system has been tested with naive user s; the results of the experiment are reported and compared with those obtai ned with other visual languages. (C) 1999 Academic Press.