Fix Orphaned SQL Users

gistfile1.sql

-- Fix orphaned users after restoring a SQL database (pre-2012 version)
USE YourDBName;
exec sp_change_users_login 'update_one', 'username', 'username';

-- Fix orphaned users after restoring a SQL database (version 2012 and after)
USE master;
CREATE LOGIN username WITH PASSWORD = 'password';
USE YourDBName;
ALTER USER username WITH LOGIN = username;