A feature of at least one object from a first computer database is selected with a graphical user interface. The feature is characterized by a value. The feature can be selected from a table in which the feature is represented as a field in the table. A subrange of values of the feature is selected with the graphical user interface from a graph of a range of values of the feature. The graph can be a histogram, a scatter plot, or the like. The query is constructed so that it can identify an object from at least one of the first computer database and a second computer database if the value of the feature of the object is within the subrange of values.