在asp mvc中从备份还原数据库

Question

我是asp mvc的新手，我正在尝试制作备份数据库并从备份文件中恢复它的操作

这里是代码

public class BackupController : Controller
{
    private RemasEntities1 db = new RemasEntities1();
    // GET: Backup
    public ActionResult BackupDatabase()
    {
        string dbPath = Server.MapPath("~/App_Data/DBBackup.bak");
        using (var db = new RemasEntities1())
        {
            var cmd = String.Format("BACKUP DATABASE {0} TO DISK='{1}' WITH FORMAT, MEDIANAME='DbBackups', MEDIADESCRIPTION='Media set for {0} database';"
                , "Remas", dbPath);
            db.Database.ExecuteSqlCommand(TransactionalBehavior.DoNotEnsureTransaction, cmd);
        }
        return new FilePathResult(dbPath, "application/octet-stream");
    }


    public ActionResult RestoreDatabase()
    {
        string dbPath = Server.MapPath("~/App_Data/DBBackup.bak");
        using (var db = new RemasEntities1())
        {

            var cmd = String.Format("restore DATABASE {0} from DISK='{1}';"
                , "Remas", dbPath);
            db.Database.ExecuteSqlCommand(TransactionalBehavior.DoNotEnsureTransaction, cmd);
        }
        return View();
    }
}

备份操作运行良好，但是当我尝试从还原操作还原数据库时，它会抛出异常

  

sql.data.sqlexception类型的例外＆＃39;发生在entityframework.sqlserver.dll中但未在用户代码中处理

     

还原无法处理数据库＆＃39; Remas＆＃39;因为它在本次会议中使用。建议在执行此操作时使用master数据库

Answer 1

尝试使用master：

var cmd = String.Format("USE master restore DATABASE Remas from DISK='{0}' WITH REPLACE;", dbPath);