4. A method comprising: generating summary records that summarize full item records, the generating of the summary records being performed by a machine; receiving a request from a user and indicative of a geographic region; and presenting at least part of a full item record among the full item records based on the generated summary records that summarize the full item records and based on the geographic region in response to the received request.
7. The method of claim 4 , wherein: the generating of the summary records generates a map file that organizes the summary records into groups; and the presenting of at least the part of the full item record among the full item records is based on the map file that organizes the summary records into groups.