How to get OSM IDs by Nominatim?

For a local installation of the OSM and Nominatim databases, is there a way to get the OSM IDs of the individual address fields returned by a Nominatim query?

For example, when two queries return the same city name, is there a way to determine whether or not this is in fact the same city, rather than two cities with the same name?

An SQL select statement or a short "how to do this in SQL" would be very much appreciated. Thanks.