How to Fix Orphaned Users

I sometimes move databases between production, test, and dev. Sometimes I backup and restore, sometimes I detach/attach the databases. Almost everytime I do this where I'm using SQL logins, I find orphaned users in the database even though I've created the user in SQL Server prior to the restore/attach.

All users are linked via a SID to a login and if you have SQL Server logins, who’s SIDs are managed by SQL Server. If the database is using Windows Logins, this does not occur because the SID is controlled by Windows or Active Directory. So, how do you fix the problem without dropping and re-creating the user? Use a stored procedure called sp_change_users_login to fix orphaned users. This stored procedure can do several things but the two things I use it for is to tell me which users are orphaned, and let me fix the user.

To find orphaned users:

USE [ESB_UR43]
GO

EXEC sp_change_users_login 'REPORT'

UserName  UserSID
--------  -----------------------------------
uni_sa    0xB0FC618806E338429B80171B88A42F00

To fix this orphaned user, I run sp_change_users_login with the UPDATE_ONE action and provide the name of the orphaned user and the name of the server user login.

USE [ESB_UR43]
GO

EXEC sp_change_users_login 'UPDATE_ONE','uni_sa','uni_sa'

Once this is completed, you should be able to manage the user mappings and permissions using the SQL Manager Tools.