We're adding single sign-on to an existing application that now requires a database table to store the external identity values (
ClaimTypes.NameIdentifier). We're adding both WSFederation and OpenIdConnect support.
From the documentation I've read and examples I've used within development, there doesn't appear to be a specification for this value.
Currently within development we are receiving non-volatile read-only values from AzureAD that cannot be edited for each user (to prevent re-use, or any amendment if somebody changes their name, etc.) that look similar to this:
However, I'm interested to know if tenants can return longer values? To help design the most efficient database/queries, is there a specification/recommendation for this value, particularly it's maximum length?