1. A method for processing and visualizing data from a data base, in which the data base contains a plurality of records, each record includes a plurality of data fields, each field contains field data, has a field name and one of a plurality of data types, the method comprising the following steps: accessing the data base and reading the records; automatically determining a range of the field data in each of the data fields; for each data field, selecting and calculating a relevance measure, the relevance measure being a predetermined, data type-dependent function indicating, for interdependent data fields, a predefined measure of relational closeness to at least one other of the data fields and, for non-interdependent data fields, a predefined measure of a data type-dependent characteristic solely of the field data in each non-interdependent data field; automatically detecting a relational structure between the fields by calculating the respective relevance measure for each of the fields; for each of the data fields, automatically selecting an initial, adjustable, graphical query device as a predetermined function of and adapted to the type and range of the corresponding field data; and displaying for viewing by a user graphical representations of the relational structures of selected ones of the fields and their corresponding initial query devices in an order determined as a predetermined function of their respective relevance measures; sensing adjustment by the user of any of the displayed, adjustable, graphical query devices; and updating the graphical representations of the relational structures corresponding to the sensed adjustments of any of the query devices, thereby enabling interactive visualization of the relational structures of the data fields.