使用 VB.NET 在 SQL LocalDB 中恢复数据库

Question

我在 VB.NET 和 SQL Server 2012 LocalDB (v11) 中开发了一个项目，我的应用程序需要 backup/restore 工具。备份部分已完成，但我卡在了恢复部分。这是我想要处理的查询（并且它在 SQL 编辑器中工作正常）

ALTER DATABASE [<.MDF File Path>] 
SET SINGLE_USER WITH ROLLBACK IMMEDIATE

RESTORE DATABASE [<.MDF File Path] FROM DISK='<.bak File Path'

这里是 VB.NET 中的代码，我正在尝试执行

Sub Restorequery(ByVal que As String)
    MainForm.Conn.Close()
    con = New SqlConnection("Data Source=(LocalDB)\v11.0;Database=Master;integrated security=True;")
    If Not con.State = ConnectionState.Open Then con.Open()
    cmd = New SqlCommand(que, con)
    cmd.ExecuteNonQuery()
End Sub

这是我目前尝试过的方法

使用与上面相同的查询

Restorequery("ALTER DATABASE [<.MDF File Path>] SET SINGLE_USER WITH ROLLBACK IMMEDIATE")
Restorequery("restore database [<.MDF File Path>] from disk='<.bak File Path>'")

这会导致错误

Exclusive access could not be obtained because the database is in use. RESTORE DATABASE is terminating abnormally.

在找到上述问题的原因后（即使在使用 master 数据库打开连接并使用 MainForm.Conn.Close() 关闭所有先前打开的连接之后也是无稽之谈），我尝试了第二次根据 Whosebug 中的一些链接和参考的方法。这是我尝试过的查询：
```
Restorequery("use [master] ")
Restorequery("alter database [<.MDF File Name>] set single_user with rollback immediate")
Restorequery("restore database[<.MDF File Name>] from disk='<.bak File Name>'")
Restorequery("alter database [<.MDF File Name>] set multi_user")
Restorequery("use [<.MDF File Name>]")
```
这是我在执行第二个查询时遇到的错误：

Additional information: User does not have permission to alter database <.MDF File Name with Path>, the database does not exist, or the database is not in a state that allows access checks. ALTER DATABASE statement failed.

是否有任何其他方法可以使用 VB.NET 恢复 SQL 服务器 LocalDB？

Answer 1

我在我的一个项目中使用过这段代码。

Try 
     With OpenFileDialog1
            .Filter = ("DB Backup File|*.bak;")
            .FilterIndex = 4
     End With

     OpenFileDialog1.FileName = ""

     If OpenFileDialog1.ShowDialog() = DialogResult.OK Then
          Cursor = Cursors.WaitCursor
          SqlConnection.ClearAllPools()
          con = New SqlConnection(cs)
          con.Open()
          Dim cb As String = "USE Master ALTER DATABASE [" & System.Windows.Forms.Application.StartupPath & "\BRH.mdf] SET Single_User WITH Rollback Immediate Restore database [" & System.Windows.Forms.Application.StartupPath & "\BRH.mdf] FROM disk='" & OpenFileDialog1.FileName & "' WITH REPLACE ALTER DATABASE [" & System.Windows.Forms.Application.StartupPath & "\BRH.mdf] SET Multi_User "
          cmd = New SqlCommand(cb)
          cmd.Connection = con
          cmd.ExecuteReader()
          con.Close()
    End If
Catch ex As Exception
    MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
    End Try

使用 VB.NET 在 SQL LocalDB 中恢复数据库

Restore database in SQL LocalDB using VB.NET

vb.net

database-restore

localdb

visual-studio-2013

sql-server-2012-localdb