Abstract: A geographic database for use with a navigation application program that provides navigation features to an end-user. The geographic database includes a plurality of data records of a first type and a plurality of data records of a second type. The plurality of records of the first type are organized into a plurality of parcels, each of which includes a plurality of data records of the first type and the plurality of records of the second type are organized into a plurality of parcels, each of which includes a plurality of data records of the second type. The parcels of data records of the first type are interleaved with the parcels of data records of the second type. This interleaving enables navigation functions that use these different types to access these different types more quickly and efficiently, thereby enhancing navigation system performance.

Abstract: A geographic database for use with a navigation application program that provides navigation features to an end-user. The geographic database includes a plurality of data records of a first type and a plurality of data records of a second type. The plurality of records of the first type are organized into a plurality of parcels, each of which includes a plurality of data records of the first type and the plurality of records of the second type are organized into a plurality of parcels, each of which includes a plurality of data records of the second type. The parcels of data records of the first type are interleaved with the parcels of data records of the second type. This interleaving enables navigation functions that use these different types to access these different types more quickly and efficiently, thereby enhancing navigation system performance.

Abstract: An improved method and system that provides for a data access interface layer in a navigation system. The navigation system is of the type that includes a navigation application software program that provides navigating features to a user of the system and a geographic database stored on a computer-readable storage medium wherein the geographical database includes information relating to the geographical region about which the navigation system provides the navigation features to the user. The data access interface layer is preferably stored in the navigation system as a library of software functions. The data access interface layer operates in conjunction with the navigation system application software. The data access interface layer isolates the navigation application software from the geographic data which are stored on the storage medium. The data access interface layer intercepts requests by the navigation application software for geographic data.

Abstract: An improved method and system that provides for a data access interface layer in a navigation system. The navigation system is of the type that includes a navigation application software program that provides navigating features to a user of the system and a geographic database stored on a computer-readable storage medium wherein the geographical database includes information relating to the geographical region about which the navigation system provides the navigation features to the user. The data access interface layer is preferably stored in the navigation system as a library of software functions. The data access interface layer operates in conjunction with the navigation system application software. The data access interface layer isolates the navigation application software from the geographic data which are stored on the storage medium. The data access interface layer intercepts requests by the navigation application software for geographic data.

Abstract: An improved method and system that provides for a data access interface layer in a navigation system. The navigation system is of the type that includes a navigation application software program that provides navigating features to a user of the system and a geographic database stored on a computer-readable storage medium wherein the geographical database includes information relating to the geographical region about which the navigation system provides the navigation features to the user. The data access interface layer is preferably stored in the navigation system as a library of software functions. The data access interface layer operates in conjunction with the navigation system application software. The data access interface layer isolates the navigation application software from the geographic data which are stored on the storage medium. The data access interface layer intercepts requests by the navigation application software for geographic data.

Abstract: A geographic database for use with a navigation application program that provides navigation features to an end-user. The geographic database includes data entities that represent segments of roads and additionally includes data entities that represent aggregations of segments of roads. The data entities that represent aggregations of segments of roads are used during a route calculation by the navigation application to suppress evaluation of roads of lesser functional rank thereby enhancing performance of the navigation system. According to one aspect, each of the data entities that represent segments of roads that represents a segment of a road that together with at least one other segment of a road forms part of an aggregation which is represented by one of the data entities that represent aggregations of segments of roads includes a reference thereto.