How to reinstall MS SQL from WorkGroup to AD DS?

Question

Active Directory

Good afternoon!
Available:
- Windows Server 2008 R2
- MS SQL 2005 Express (~2.5GB database)
- AD DS (name.domain.ru)
Required:
- Reinstall MS SQL 2005 to work from the domain, before that the server was in the workgroup, now in the domain.
Question:
- What needs to be done for a complete reinstallation of MS SQL

Answer 1

twist everything into a backup,
raise it in the SQL domain, write the same alias, expand the backup, profit.

Answer 2

What is the difference between "domain work" and "workgroup" for you?
I think you can do without reinstallation.
Do you need to allow authorization of domain users in SQL, or would SQL itself work as a domain user?