MAP UPDATE DATA SUPPLYING APPARATUS, VERSION TABLE, MAP DATA UPDATING SYSTEM AND MAP UPDATE DATA SUPPLYING METHOD

摘要

An object of the present invention is to keep the data amount of update data files to a small level, while guaranteeing the integrity between sections that are positioned adjacent to each other even after an update requesting section has been updated in response to a request from a navigation apparatus, and also to keep the data amount of a data table used for realizing the update to a small level. The present invention includes a version table VT, an obtaining unit 9, and a generating unit 10. The version table VT stores therein information related to guaranty versions va in correspondence with section groups g. Each of the section groups g is a set made up of a different one of sections p in update-purpose map data Ma and another section p that is positioned adjacent thereto. Each of the guaranty versions va is an oldest update version that is able to guarantee the integrity between the sections p that constitute a corresponding one of the section groups g. By referring to the version table VT, the obtaining unit 9 extracts update requiring sections pb and obtains the information related to the guaranty versions va respectively corresponding to the extracted update requiring sections pb. Each of the update requiring sections pb is one of the sections that needs to be updated in order to guarantee the integrity between the sections p that are positioned adjacent to each other after the update requesting section pa has been updated. The generating unit 10 generates update data files fa based on an update-purpose map database DBl.