如何避免 MSSql 2000 中出现错误“已存在与此命令关联的打开 DataReader”

Posted 2023-05-07

【中文标题】如何避免 MSSql 2000 中出现错误“已存在与此命令关联的打开 DataReader”

【英文标题】：How to avoid Error "There is already an open DataReader associated with this Command" in MSSql 2000

【发布时间】：2014-08-26 10:21:35

【问题描述】：

我正在使用 SqlBulkCopy 将数据复制到同一数据库中的 2 个单独的表中。

obj_Command.CommandText = "Select * from  tmpInvDtlMast where InvNo='111'"



Using bulkCopy As SqlBulkCopy = New SqlBulkCopy(con1)
                        bulkCopy.DestinationTableName = "tmpInvDtlMast"

                        Try

                            bulkCopy.WriteToServer(obj_Command.ExecuteReader())
                            Application.DoEvents()

                        Catch ex As Exception
                            Console.WriteLine(ex.Message)
                        Finally
                            bulkCopy.Close()

                        End Try
                    End Using


                        Using bulkCopy As SqlBulkCopy = New SqlBulkCopy(con1)
                            bulkCopy.DestinationTableName = "InvDtlMast"

                            Try

                                bulkCopy.WriteToServer(obj_Command.ExecuteReader())
                                Application.DoEvents()

                            Catch ex As Exception
                                Console.WriteLine(ex.Message)
                            Finally
                                bulkCopy.Close()
                            End Try
                        End Using

在第二次批量上传时出现此错误

已经有一个打开的 DataReader 与此命令关联

我已尝试使用我的连接字符串“MultipleActiveResultSets=true”

con1.ConnectionString = "Data Source=" & SqlServer & ";Initial Catalog=" & Database & ";Persist Security Info=True;User ID=" & User & ";Password=" & Pass & ";MultipleActiveResultSets=true"

在谷歌搜索更多解决方案后，我知道 MultipleActiveResultSets=true 不支持 MSSql 2000。在 Sql2000 中有什么办法可以解决这个问题。请帮忙

我正在使用 vb.net 2008

【参考方案1】：

作为一种解决方法，尝试复制连接和命令：

obj_Command.CommandText = "Select * from  tmpInvDtlMast where InvNo='111'"

Using bulkCopy As SqlBulkCopy = New SqlBulkCopy(con1)
    bulkCopy.DestinationTableName = "tmpInvDtlMast"

    Try
        bulkCopy.WriteToServer(obj_Command.ExecuteReader())
        Application.DoEvents()

    Catch ex As Exception
        Console.WriteLine(ex.Message)
    Finally
        bulkCopy.Close()

    End Try
End Using


Using bulkCopy As SqlBulkCopy = New SqlBulkCopy(**con2**)
    bulkCopy.DestinationTableName = "InvDtlMast"

    Try
        bulkCopy.WriteToServer(**obj_Command2**.ExecuteReader())
        Application.DoEvents()

    Catch ex As Exception
        Console.WriteLine(ex.Message)
    Finally
        bulkCopy.Close()
    End Try
End Using

【讨论】：

@SajithaRathnayake 请分享您的解决方案

【参考方案2】：

我自己解决了我的问题。我所做的是删除

obj_Command.ExecuteReader()

带有新的 SqlDataReader 实例。

obj_Command.CommandText = "Select * from  tmpInvDtlMast where InvNo='111'"
Dim dr as SqlDataReader()
dr=obj_Command.ExecuteNoneQuery()

               Using bulkCopy As SqlBulkCopy = New SqlBulkCopy(con1)
                    bulkCopy.DestinationTableName = "tmpInvDtlMast"

                    Try

                        bulkCopy.WriteToServer(dr)
                        Application.DoEvents()

                    Catch ex As Exception
                        Console.WriteLine(ex.Message)
                    Finally
                        dr.Close()

                    End Try
                End Using


                    Using bulkCopy As SqlBulkCopy = New SqlBulkCopy(con1)
                        bulkCopy.DestinationTableName = "InvDtlMast"

                        Try

                            bulkCopy.WriteToServer(dr)
                            Application.DoEvents()

                        Catch ex As Exception
                            Console.WriteLine(ex.Message)
                        Finally
                            dr.Close()
                        End Try
                    End Using