| 摘要 |
PROBLEM TO BE SOLVED: To realize a fine updating unit so as to prevent a non-contiguous link or node from constituting a single updating unit due to the presence of data commonly referred to from a plurality of links or nodes.SOLUTION: A map data distribution server, including an update data storage part for storing an update element for updating data among maps of a plurality of generations, includes: a dependent relation storage part for storing a dependent relation between update elements; and an update element correlation storage part for storing correlation between update elements. Further, an update element including an update target element of a requested map is retrieved from the update data storage part, and an update element having a dependent relation or correlation with the retrieved update element is retrieved from the dependent relation storage part and an update unit data correlation storage part, to distribute the retrieved update element together with the update element retrieved from the update data storage part. |
