Anyone have tricks in Diagnostic Manager to determine databases that haven't been used? There are a lot of T-SQL scripts floating around, all of which seem to not be very accurate in my experience.
For SQL Server? Assuming you want to know if anyone logs in at all:Audit logins?https://docs.microsoft.com/en-us/sql/ssms/configure-login-auditing-sql-server-management-studio
I'm looking for specific database, not entire instances. Unfortunately, login auditing does not help with this, unless you have perfectly coupled service accounts and databases, which I've rarely seen in any shop.
Av logon trigger should do it, then. You can track which database gets accessed.https://www.mssqltips.com/sqlservertip/3171/identify-sql-server-databases-that-are-no-longer-in-use/
Using this information, I would then build a filtered report to see what queries they're actually running.