3. Perspective Three?Database assisted, or pure calculated code
Some code needs database access, or at least have pattern table, in order to encode/decode. For example, MapCode™ needs data of the first mesh coordinate, StatusQuo needs information of origin point of each cities.
Database assisted type can be make code shorter, and can be asymmetric. It is possible to assign short code for cities, and long code for ocean, etc. However, database should work with it, and it may require network communication. In case of disaster and communication line is disabled, it is difficult to use.

Other codes can be encoded/decoded by pure calculation only with latitude/longitude. For example, NAC, LocaPoint, LP-Address, GeoPo, and N-Code etc. can be converted directly from latitude and longitude with some simple equations. This makes implementation easy, and can be independent from network connection status.