MAP DATA STORAGE DEVICE, MAP DATA UPDATING METHOD, AND COMPUTER PROGRAM

A map data storage device, a map data updating method, and a computer program that can shorten the time required for a map data updating process compared to the related art are provided. In the case where map data 46 stored in a navigation-side local DB 45 of a navigation apparatus 1 are to be updated, the navigation apparatus 1 updates the map data 46 stored in the navigation-side local DB 45 on the basis of map updating data received from a map distribution center 3, and prepares a data reference index 47 that associates a PID (universal identification information) included in the map data 46 with a record number (internal identification information) included in the map data 46 on the basis of the updated map data 46. After that, in the case where an application is executed by the navigation apparatus 1, the prepared data reference index 47 is referenced to access the map data 46 stored in the navigation-side local DB 45.