Context

An Object Identifier must be globally unique across an entire database. By default, objects have identifiers in the Global or null Context. For an object in this default Context, the object ID must be globally unique. When a Context is specified, an ID only needs to be unique within the namespace represented by that Context. Any ID can serve as the Context for any other Identifier. In the following example, a PUMP is given an ID in the context of the ID of a PLANT:

If the ID of an object is unique within the database, it can be referred to by its short ID, for example "P-101". To make sure that an ID refers to a single object the Context must be supplied as well: "WCP|P-101". Context is not limited to just one level but can be chained without limit.

Note: The use of the convention used in the AIM Workhub of a vertical bar (|) to separate the Context from the ID (however, this is not valid in the AIM Workhub XML Schema) and the use of Context should be regarded as mandatory. It is in any case unavoidable when one database contains information from two or more PLANTS or PROJECTS to prevent clashes of identifier between the two sets of data. In an AIM Workhub Import Package, it is necessary to declare a Root Object and the ID of this object is normally used as the Context for all the objects in that Import Package.