<p>A method and apparatus for accessing a database where entries are linked to at least two sets of patterns. Recognition means recognise within a received signal one or more patterns of a first set of patterns. The recognised patterns are used to identify entries and compile a list of patterns in a second set of patterns to which those entries are also linked. The list is then used to recognise a second received signal. The received signals may, for example, be voice signals or signals indicating the origin or destination of the received signals. <IMAGE></p>