How to restore SQL Server database through C# code

Question

I try to restore the database like this:

SQL = @\"RESTORE DATABASE MyDataBase TO DISK=\'d:\\MyDATA.BAK\'\";
                Cmd = new SqlCommand(SQL, Conn);
         


        

Answer 1

I've ended with this solution. Name of my database was Stats This will work without installed MSSQL management studio

    public void BackUpDB(string fname)
    {
        using (SqlConnection cn = new SqlConnection(_cstr))
        {
            cn.Open();
            string cmd = "BACKUP DATABASE [Stats] TO DISK='" + fname + "'";
            using (var command = new SqlCommand(cmd, cn))
            {
                command.ExecuteNonQuery();
            }
        }
    }

    public void RestoreDB(string fname)
    {
        using (SqlConnection cn = new SqlConnection(_cstr))
        {
            cn.Open();
            #region step 1 SET SINGLE_USER WITH ROLLBACK
            string sql = "IF DB_ID('Stats') IS NOT NULL ALTER DATABASE [Stats] SET SINGLE_USER WITH ROLLBACK IMMEDIATE";
            using (var command = new SqlCommand(sql, cn))
            {
                command.ExecuteNonQuery();
            }
            #endregion
            #region step 2 InstanceDefaultDataPath

            sql = "SELECT ServerProperty(N'InstanceDefaultDataPath') AS default_file";
            string default_file = "NONE";
            using (var command = new SqlCommand(sql, cn))
            {
                using (var reader = command.ExecuteReader())
                {
                   if (reader.Read())
                    {
                        default_file = reader.GetString(reader.GetOrdinal("default_file"));
                    }
                }
            }
            sql = "SELECT ServerProperty(N'InstanceDefaultLogPath') AS default_log";
            string default_log = "NONE";
            using (var command = new SqlCommand(sql, cn))
            {
                using (var reader = command.ExecuteReader())
                {
                    if (reader.Read())
                    {
                        default_log = reader.GetString(reader.GetOrdinal("default_log"));
                    }
                }
            }
            #endregion
            #region step 3 Restore
            sql = "USE MASTER RESTORE DATABASE [Stats] FROM DISK='" + fname + "' WITH  FILE = 1, MOVE N'Stats' TO '" + default_file + "Stats.mdf', MOVE N'Stats_Log' TO '"+ default_log+ "Stats_Log.ldf', NOUNLOAD,  REPLACE,  STATS = 1;";
            using (var command = new SqlCommand(sql, cn))
            {
                command.ExecuteNonQuery();
            }
            #endregion
            #region step 4 SET MULTI_USER
            sql = "ALTER DATABASE [Stats] SET MULTI_USER";
            using (var command = new SqlCommand(sql, cn))
            {
                command.ExecuteNonQuery();
            }
            #endregion
        }
    }

Answer 2

Your connection string should have a master database as default catalog to connect to.

Answer 3

  public void Restore(string Filepath)
        {
            try
            {
                if(con.State == ConnectionState.Closed)
                {
                    con.Open();
                }
                SqlCommand cmd1 = new SqlCommand("ALTER DATABASE [" + Database + "] SET SINGLE_USER WITH ROLLBACK IMMEDIATE ", con);
                cmd1.ExecuteNonQuery();
                SqlCommand cmd2 = new SqlCommand("USE MASTER RESTORE DATABASE [" + Database + "] FROM DISK='" + Filepath + "' WITH REPLACE", con);
                cmd2.ExecuteNonQuery();
                SqlCommand cmd3 = new SqlCommand("ALTER DATABASE [" + Database + "] SET MULTI_USER", con);
                cmd3.ExecuteNonQuery();
                con.Close();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
            con.Close();
        }

Answer 4

You must connect to the database server via a different database.

So your connection string should take you to say "Master" or another database on the server, then you can complete the task at hand.

Answer 5

Your DB connection is most likely to the database you're trying to restore. So there is a DB shared lock which prevents the restore of your db

Try this

SQL = @"USE master BACKUP DATABASE MyDataBase TO DISK='d:\MyDATA.BAK'";

Or change the connection details to use master DB

Answer 6

I prefer to use SMO to restore a backup:

Microsoft.SqlServer.Management.Smo.Server smoServer = 
     new Server(new ServerConnection(server));

Database db = smoServer.Databases['MyDataBase'];
string dbPath = Path.Combine(db.PrimaryFilePath, 'MyDataBase.mdf');
string logPath = Path.Combine(db.PrimaryFilePath, 'MyDataBase_Log.ldf');
Restore restore = new Restore();
BackupDeviceItem deviceItem = 
    new BackupDeviceItem('d:\MyDATA.BAK', DeviceType.File);
restore.Devices.Add(deviceItem);
restore.Database = backupDatabaseTo;
restore.FileNumber = restoreFileNumber;
restore.Action = RestoreActionType.Database;
restore.ReplaceDatabase = true;
restore.SqlRestore(smoServer);

db = smoServer.Databases['MyDataBase'];
db.SetOnline();
smoServer.Refresh();
db.Refresh();

You'll need references to Microsoft.SqlServer.Smo, Microsoft.SqlServer.SmoExtended, and Microsoft.SqlServer.Management.Sdk.Sfc