In my opinion, there should not exist any placeholder for Foreign Keys. If a FK is mandatory, you need to publish it. If not, just make
David Horat [mailto:david.horat@cern.ch] said: them optional. If you put a placeholder in a FK, then the word mandatory has no real meaning. It's really the other way around, if an attribute is mandatory you have to publish *something*, even if for some reason the info provider is unable to determine the correct value. In the particular case I encountered (Policy -> UserDomain) I think it is a mistake for it to be mandatory, but there are other cases, e.g. ToComputingService -> ComputingService, where it clearly is correct for it to be mandatory but nevertheless the info provider may for some reason fail to determine the correct ID. You then want a value which is clearly erroneous so you can detect the failure. Also for example the way the gip works is to have a template file, with values which should be changed by the dynamic provider. If that provider fails the values in the template will become visible, and again you want to use something which is easily detectable. Stephen -- Scanned by iCritical.