The guid accessor generates a pseudo-unique guid. The result is a document with a root element <guid> containing the identifier. Here is an example:

Note: The guid accessor generates the guid based upon a set of pseudo-random inputs, including an optional seed operand document. It has not been certified to generate a guaranteed globally unique ID. However for applications that require convenient session tokens and which provide unique seed documents the generated guids will be locally unique.

If your application requires truely globally unique ID's we recommend you customize the guid accessor.