minor
defect
major
minor
minor
#28816
Reference value attributes only generate errors with SingleSelection
If there is data in the system such that a reference-type, multi-valued (multiple) attribute points to an object that no longer exists (because it was deleted during a migration, for example), does this result in an error if exactly this one object is referenced in this attribute? (Good)
However, if multiple objects are referenced in the attribute—some of which exist and some of which do not—this does not result in an error. (Bad)
Migration
When resolving a multi-valued reference attribute, any reference to an object that no longer exists now results in a KnowledgeBaseRuntimeException (InvalidLinkException, "Dangling references to no longer existing objects"). Previously, such entries were silently ignored as long as at least one other referenced object existed.
Data sets in which objects were deleted without cleaning up the incoming references (e.g., due to a previous migration) must be cleaned up before the update; otherwise, reading the affected attributes will fail at runtime. Custom migrations that delete objects must also remove the references to those objects.