We default to NULL in DB for authorised_values.lib but actually we should require a description. Or dropdown lists will have an empty option. For the atomic update we should fix existing data and retrieve the code.
Katrin, could you confirm this assumption?
In the past it was sometimes necessary to add an empty entry manually, as the pull downs would not offer one otherwise. So such entries might exist in the existing databases for a reason. I am not sure if they are still needed. How would a fix with the atomicupdate look like? Would we aim for deleting such entries? I believe just removing them could cause issues: a pull down that does not offer an empty entry on its own, would jump to the first entry in list, which would result in saving/displaying wrong values in forms.