Visual strategies for querying databases

A number of interfaces, based on different techniques which better exploit the human senses, have been recently suggested and implemented so enlarging the bandwidth of the man-machine communication channel. The availability of graphical devices at low cost has given rise to a large diffusion of visual interfaces. The database field is particularly suited for such interfaces mainly because the database is often queried by a casual user, who may not be conversant with conventional query languages. The use of a visual tool may therefore help to access the database, without the dependency on the native language and the limitations imposed by the specific application area. The authors concentrate on the querying strategies developed in existing visual query systems (VQS) by defining a suitable taxonomy and analyzing how these systems can be compared against such a taxonomy