How can I get all picklist values in a validation rule?
I'm looking for a suitable function but I cannot find any.
What I need to achieve is that some string is among the picklist values.
Please advise.
There is no such function to get all picklist values. You can enable the "Strictly Enforce Picklist Values" function for a picklist, or use Apex code, but Validation Rules won't get you where you want to go.
