What is jcr:uuid? When it will be generate?

[akshaybhujbale]

What is jcr:uuid? When it generate after page or asset creation or after publishing?

Is it a default property? 

[Jagadeesh_Prakash · Accepted solution]

@akshaybhujbale The jcr:uuid property is a protected, auto-created, mandatory property. This means that it is created and administered by the system and can only be read (but not changed or deleted) by the client. The job of the jcr:uuid property is to expose the universally unique identifier (UUID) of its node

https://developer.adobe.com/experience-manager/reference-materials/spec/jcr/1.0/4.9_Referenceable_No....

[akshaybhujbale]

Thanks @Jagadeesh_Prakash 

When it will be created after creating page/assets or after publishing it?

Also what are the protected and auto created properties?

[Jagadeesh_Prakash]

@akshaybhujbale 

Once can note that jcr:uuid indeed was considered as a candidate initially, but was not further considered since:

When asset is replicated to publish instance then on publish instance new jcr:uuid will be created.
As per section 3.3 of JCR 2.0 spec , this identifier is unique in the workspace, but it never guarantees lifetime uniqueness