Catalogued data is one of the ways information will be collected from VO. The selected material will contain many physical quantities (columns) and in an increasing number of cases, a large number of sources (rows). The larger the catalog, the more interesting it becomes from an statistical point of view. However, describing the parameter space coverage of any catalogue is not a trivial task and neither it is to envision relationships. Besides the need for developing automated methods of data exploration, visualisation techniques contribute enormously to get a good idea of the global properties of a catalogue and to select regions of interest in the parameter space without actually moving large data chunks. A method which associates a database system (datoz, Ortiz, 1998), and a Java graphics interface (Köppen, 2001) is presented as one approach to solve this problem.