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我正在尝试将记录从一个 SQL Server 表复制到另一个。两个表具有相同的结构，其中一列是 xml 类型。源表的行中有很大的 xml 内容，大约 2.5Mb。

我将 xml 列的内容保存到文件中，请参阅附加的 map.zip 或从 https://docs.google.com/leaf?id=0Bz4PXXEQL5TpM2U5MWJhM2MtMTI0Yi00ODg0LTk4OWItMzJiNjVjMDIzNjc2&hl=en&authkey=CLT5i8oP下载

我的代码的简化版本：

string query = "select * from MyTableSource where id = 1";

using (SqlConnection targetConnection = new SqlConnection(connectionStringTarget))
{
targetConnection.Open();

using (SqlConnection sourceConnection = new SqlConnection(connectionStringSource))
{
    sourceConnection.Open();

    using (SqlCommand command = new SqlCommand(query, sourceConnection))
    {
    using (IDataReader reader = command.ExecuteReader(CommandBehavior.SingleResult))
    {
        using (SqlBulkCopy bulkCopy = new SqlBulkCopy(targetConnection))
        {
        bulkCopy.DestinationTableName = "MyTableTarget";
        bulkCopy.WriteToServer(reader);
        }
    }
    }
} 
}

bulkCopy.WriteToServer 上发生的异常：

System.Data.SqlClient.SqlException was unhandled
Message=XML parsing: Document parsing required too much memory
Source=.Net SqlClient Data Provider
ErrorCode=-2146232060
Class=16
LineNumber=1
Number=6303
Procedure=""
Server=myserver
State=1
StackTrace:
     at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection)
     at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning()
     at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj)
     at System.Data.SqlClient.SqlBulkCopy.WriteToServerInternal()
     at System.Data.SqlClient.SqlBulkCopy.WriteRowSourceToServer(Int32 columnCount)
     at System.Data.SqlClient.SqlBulkCopy.WriteToServer(IDataReader reader)
     at SyncTest.Form1.buttonCopyXml_Click(Object sender, EventArgs e) in C:\..\Form1.cs:line 2251
     at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
     at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
     at System.Windows.Forms.Control.WndProc(Message& m)
     at System.Windows.Forms.ButtonBase.WndProc(Message& m)
     at System.Windows.Forms.Button.WndProc(Message& m)
     at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
     at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
     at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
     at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
     at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
     at SyncTest.Program.Main() in C:\..\Program.cs:line 18
     at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
     at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
     at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
     at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
     at System.Threading.ThreadHelper.ThreadStart()
InnerException:

它看起来像一个 SqlBulkCopy 错误。我想知道是否有人可以复制并确认这一点。

更新： 提交给微软，

_https://connect.microsoft.com/VisualStudio/feedback/details/614046/sqlbulkcopy-fails-trying-to-copy-a-row-with-large-content-in-an-xml-column

他们确认这是他们的错误：

从到目前为止的调试来看，看起来像是批量复制路径中 XML 的服务器端处理存在问题。XML 文件中的属性之一非常大，这导致 SQL Server 在处理 XML 时由于分配大小限制而失败。

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1 回答 1

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更改您的选择查询以将 xml 列检索为 [n]varchar(max) 列类型，以避免 xml 处理开销，以及可能的错误。

于 2011-01-28T11:34:24.470 回答