1. A method of building and maintaining an object-oriented database from a vector product format (VPF) database, comprising: instantiating objects of the object-oriented database, using the VPF database; initializing spatial and non-spatial feature data of the object-oriented database, spatially indexing data among objects across hierarchical levels of the objectoriented database; and updating data of the object-orientated database; and exporting the contents of the updated object-oriented database to teh VPF database.