I'm trying to identify users who have obtained access but not utilized Tableau.
Using the system_users table, Created At field, i am calculating the days since obtaining access and will notify those with >90 days that they should use the software or cancel their license.
However, I'm finding that 20% of the users have a Null value for Created At.
We grant access via Active Directory groups mapped to Tableau Groups, and so all users are added when the groups synchronize.
I can't find a common attribute: old users as well as newly added; some have logged in, others have not; all site roles, etc.
Does anyone have experience with this?
Do you know the causes?