无法更新当前锁定的vb.net错误

Question

我想在2个不同的table of ms-access中插入2个不同的数据。

它显示了这个错误。

我有这样的代码：

try
 dim sql1,sql2 as string
 sql1 = "INSERT INTO table1(something)VALUES(something)"
 cmd = new oledbcommand(sql1, connection)
 cmd.executenoquery()

 sql2 = "INSERT INTO table2(something)VALUES(something)"
 cmd2 = new oledbcommand(sql2, connection)
 cmd2.executenoquery()
catch ex as exception
  msgbox(ex.tostring())

(where these cmd1,cmd2 are defined in controlModule.)

所以，我该怎么办？

感谢任何帮助。谢谢

Answer 1

我认为关闭连接可以解决问题，最好使用Using语句：

try
    Using con As OleDbConnection = GetConnection() ' or New OlebConnection(...)
        Using cmd = con.CreateCommand()
            cmd.CommandText = "INSERT INTO table1(something)VALUES(@something)"
            cmd.Parameters.AddWithValue("@something", something)
            con.Open()
            cmd.ExecuteNonQuery()
        End Using
    End Using 

    Using con As OleDbConnection = GetConnection()
        Using cmd = con.CreateCommand()
            cmd.CommandText = "INSERT INTO table2(something)VALUES(@something)"
            cmd.Parameters.AddWithValue("@something", something)
            con.Open()
            cmd.ExecuteNonQuery()
        End Using
    End Using 
Catch ex As Exception
    msgbox(ex.tostring())
End Try 

Answer 2

这是一个并发问题。因为代码的某些其他部分或MS Access本身同时访问数据库。 事实是，您在使用后不会关闭连接。所以第二次调用应该失败并带有异常。相反，你应该包裹你的一次性用品 - 例如OleDbConnection，命令等 - 在using语句中。这样，即使发生异常，连接也将关闭：

    Using con As New OleDbConnection, cmd1 As OleDbCommand = con.CreateCommand, cmd2 As OleDbCommand = con.CreateCommand()
        cmd1.CommandText = "INSERT INTO table1(something)VALUES(something)"
        cmd1.ExecuteNonQuery()

        cmd2.CommandText = "INSERT INTO table2(something)VALUES(something)"
        cmd2.ExecuteNonQuery()
    End Using