SQL Interview: 73 Orphaned users

This is a post in the SQL Interview series. These aren’t trick or gotcha questions, they’re just questions designed to scope out a candidate’s knowledge around SQL Server and Azure SQL Database.

Section: Administration Level: Medium

Question:

In SQL Server, what is an orphaned user?

How do users typically become orphaned?

Answer:

An orphaned user is one that appears in a database, but the server principal that they are linked to, does not exist.

A common cause of orphaned users is restoring a database from another server where SQL logins were defined, but those users do not exist on the server where the restore is performed.

2025-08-24