| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a map data management apparatus for updating map data stored in a storage device wherein the map data are updated in restricted storage resources of the storage device, and a restriction on the usage of the map data during the update of the map data is reduced to the minimum. <P>SOLUTION: When updating old map data stored on a HDD 3a to new map data, a low-priority portion of the old map data that has less importance/necessity in use is deleted (b) to create a vacant area, and a high-priority portion of the new map data is updated and stored (c) to the vacant area as an update of the map data. Then, the high-priority portion of the old map data is deleted (d) to create another vacant area, and a low-priority portion of the new map data is stored (e) to the vacant area. During the update of the map data, restrictions on the usage of the map data are avoided as much as possible by having the high-priority portion having more importance/necessity in use maintained on the HDD 3a irrespective of whether the data are old or new. <P>COPYRIGHT: (C)2009,JPO&INPIT |
