1. A method for updating a first navigation database, comprising: compiling source objects stored as records in blocks of the first navigation database to generate derived objects of the first navigation database, the source objects including objects at a lowest organizational level of a map and derived objects including objects derived from source objects at a higher organizational level; compiling a subset of source objects of a second navigation database to generate derived objects of the second database, where the source objects of the second navigation database are stored as records in blocks corresponding to the blocks of the first navigation database, and where the subset includes source objects of the second navigation database that differ from the corresponding source objects specified in the first navigation database; comparing the blocks of the first navigation database having the derived objects of the first navigation database with the corresponding blocks of the second navigation database having the derived objects of the second navigation database to determine blocks of the second navigation database that differ from the corresponding blocks of the first navigation database; and generating an update package for the first navigation database comprising the blocks of the second navigation database that differ from the corresponding blocks of the first navigation database; after the step of compiling the source objects of the first navigation database, grouping the source objects and the derived objects of the first navigation database in blocks of the first navigation database; and after the step of compiling the source objects of the second navigation database, grouping the source objects and the derived objects of the second navigation database in blocks of the second navigation database; where the first navigation database comprises dependency information associated with the derived objects of the first navigation database; where the dependency information comprises information about dependencies of the derived objects on source objects or on other derived objects.