Hello,
According to this: https://msdn.microsoft.com/en-us/library/hh231028(v=sql.120).aspx
2014 version of MDS does not support @UserName parameter for stg.udp_ type of stored procedures, unlike 2016 version.
After checking the procedures I found that it uses an internal @User_ID = 0 that is said to be used for logging. Is there more information on this? So far I found only this:
I am thinking about manually creating a user with id 0 in MDS user list to have its name used for logging, will that work? Do I need to change anything else besides the user table in that case?