How are Codes and Literals handled in Global Justice XML Data Model (GJXDM)?
The source data requirements analyzed by the XML Structure Task Force (XSTF) were not consistent in their use of codes. For components with the same meaning, some sources used codes; others used literals. When codes were used, they were not always drawn from the same code table, and some code tables are specific to local jurisdictions.
In order to provide maximum flexibility, the GJXDM usually provides both a code type element and a text type element (that may contain a literal). There are particular code tables that are always common; for example National Criminal Information Center (NCIC)-2000 and the American Association of Motor Vehicle Administrators (AAMVA). Therefore, the XSTF provided a mechanism to use codes from other namespaces. This enables the use of standards without restriction to a single internal set of values.
This also does not require a change to the GJXDM namespace every time external standards change. For example, the XSTF has created an NCIC-2000 schema in its own namespace that contains the NCIC code tables. Temporarily, the XSTF refers to this as the NCIC-2000 proxy schema because it is external to the GJXDM namespace and can be updated without causing the GJXDM to change. The XSTF anticipates that local jurisdictions will want to create their own proxy schemas for their local code tables as well.