如何以编程方式恢复SQL本地数据库

Question

我正在尝试为Windows窗体应用程序创建备份和恢复功能。

所以，我试图做一个数据库恢复。我的代码是这样的：

string cbdfilename = "c:\\Users\\Public\\Public Document"; 
SqlConnection.ClearAllPools(); 
SqlConnection con = new SqlConnection("Data Source=(LocalDB)\\v11.0;AttachDbFilename=|DataDirectory|\\BbCon.mdf;Integrated Security=True;Connect Timeout=30;"); 
string sql; 

sql = "Use master;Alter Database BbCon Set Single_User With Rollback Immediate;Restore Database BbCon From Disk = @FILENAME With Replace;Alter Database BbCon Set Multi_User;"; 

SqlCommand cmd = new SqlCommand(sql, con); 
cmd.Parameters.AddWithValue("@FILENAME", cbdfilename); 

con.Open(); 

try 
{ 
    cmd.ExecuteNonQuery(); 
} 
catch(Exception ex) 
{ 
    MessageBox.Show("Restore DB failed" + ex.ToString()); 
} 
finally 
{ 
    con.Close(); 
    con.Dispose(); 
} 

但是当我尝试运行此，我得到一个错误：

Restore db failed System.Data.SqlClient.SqlException(0X80131904):userdoesnot have permission to alter database BbCon.mdf the database doesnot exist or or datbase is not in a state that allows access checks.

谁能帮助我吗？

Answer 1

您是否正在备份或恢复？您在标题中提到了备份，并且该命令用于恢复。

对于localDB还没有太多的例子。

利用我的代码如下。希望这有助于..

对于备份 -

string master_ConnectionString = @"Data Source=(LocalDB)\MSSQLLocalDB;Database=Master;Integrated Security=True;Connect Timeout=30;"; 

using (SqlConnection masterdbConn = new SqlConnection()) 
{ 
    masterdbConn.ConnectionString = master_ConnectionString; 
    masterdbConn.Open(); 

    using (SqlCommand multiuser_rollback_dbcomm = new SqlCommand()) 
    { 
     multiuser_rollback_dbcomm.Connection = masterdbConn; 
     multiuser_rollback_dbcomm.CommandText= @"ALTER DATABASE yourdbname SET MULTI_USER WITH ROLLBACK IMMEDIATE"; 

     multiuser_rollback_dbcomm.ExecuteNonQuery(); 
    } 
    masterdbConn.Close(); 
} 

SqlConnection.ClearAllPools(); 

using (SqlConnection backupConn = new SqlConnection()) 
{ 
    backupConn.ConnectionString = yourConnectionString; 
    backupConn.Open(); 

    using (SqlCommand backupcomm = new SqlCommand()) 
    { 
     backupcomm.Connection = backupConn; 
     backupcomm.CommandText= @"BACKUP DATABASE yourdbname TO DISK='c:\yourdbname.bak'"; 
     backupcomm.ExecuteNonQuery(); 
    } 
    backupConn.Close(); 
} 

对于Restore-

string master_ConnectionString = @"Data Source=(LocalDB)\MSSQLLocalDB;Database=Master;Integrated Security=True;Connect Timeout=30;"; 

using (SqlConnection restoreConn = new SqlConnection()) 
{ 
    restoreConn.ConnectionString = master_ConnectionString; 
    restoreConn.Open(); 

    using (SqlCommand restoredb_executioncomm = new SqlCommand()) 
    { 
     restoredb_executioncomm.Connection = restoreConn; 
     restoredb_executioncomm.CommandText = @"RESTORE DATABASE yourdbname FROM DISK='c:\yourdbname.bak'"; 

     restoredb_executioncomm.ExecuteNonQuery(); 
    } 
    restoreConn.Close(); 
} 

更新 -

哎呀，对不起，我的代码是SQL的LocalDB 2014但似乎你'使用2012. 请将（LocalDB）\ MSSQLLocalDB替换为（LocalDB）\ v11.0

只要尝试一下上面的更改。

根据我的经验，如果我写了|数据目录|在我的connectionString中，我只能读取（SQL SELECT命令）数据库。换句话说，插入和更新命令可以完成，但是没有任何例外，数据库没有被插入或更新。我认为设置为|数据目录|会将数据库设置为只读，我发现有些人在使用|数据目录|插入或更新数据库时遇到困难设置。

希望你的美好时光！谢谢 ！