Suppose you want to update a field in a database table based on row number, and you want to start with 20000.

There are two types of login authentication on SQL Server 2008, Windows authentication and SQL authentication.

If you try to delete a user from SQL Serve 2008 and receive this error:
the database principal owns a schema in the database, and cannot be dropped. (Microsoft SQL Server, Error :15138)
like the error message suggests, that has something to do with a schema related to it.