4

我在 Windows 7(版本 6.1 Build 7601:Service Pack 1)和 Visual Studio 2010 上有 SQL Server Express 2008 SP1。

我正在尝试使用以下代码创建一个用于将文件插入文件流的存储过程 CLR。

using System;
using System.Data;
using System.Data.SqlClient;
using System.Data.SqlTypes;
using Microsoft.SqlServer.Server;
using System.IO;
using System.Security.Principal;

public partial class StoredProcedures
{
     [Microsoft.SqlServer.Server.SqlProcedure]
     public static void sp_fileController(String friendlyName, String filePath)
{
    SqlParameter fDataParam = new System.Data.SqlClient.SqlParameter("@fData", SqlDbType.VarBinary, -1);
    SqlParameter fNameParam = new System.Data.SqlClient.SqlParameter("@fName", SqlDbType.NVarChar, 300);

    WindowsIdentity newId = SqlContext.WindowsIdentity;
    WindowsImpersonationContext impersonatedUser = newId.Impersonate();

    try
    {
        string cs = @"Server=[myservername];Integrated Security=true";
        using (SqlConnection con = new SqlConnection(cs))
        {
            con.Open();
            SqlTransaction objSqlTran = con.BeginTransaction();

            //string sql = "INSERT INTO fileStreamTest VALUES ((Cast('' As varbinary(Max))), @fName, default); Select fData.PathName() As Path From fileStreamTest Where fId = SCOPE_IDENTITY()";//OUTPUT inserted.fid 
            SqlCommand insertFileCommand = con.CreateCommand();

            insertFileCommand.Transaction = objSqlTran;

            insertFileCommand.CommandText = "INSERT INTO fileStreamTest.dbo.fileStreamTest (RowGuid, fData) VALUES (@FileID, CAST ('' as varbinary(max)))";

            Guid newFileID = Guid.NewGuid();

            insertFileCommand.Parameters.Add("@FileID", SqlDbType.UniqueIdentifier).Value = newFileID;

            insertFileCommand.ExecuteNonQuery();

            SqlCommand getPathAndTokenCommand = con.CreateCommand();

            getPathAndTokenCommand.Transaction = objSqlTran;

            getPathAndTokenCommand.CommandText =
                "SELECT fData.PathName(), GET_FILESTREAM_TRANSACTION_CONTEXT() " +
                "FROM   fileStreamTest.dbo.fileStreamTest " +
                "WHERE  rowGuid = @FileID";

            getPathAndTokenCommand.Parameters.Add("@FileID", SqlDbType.UniqueIdentifier).Value = newFileID;

            SqlDataReader tokenReader = getPathAndTokenCommand.ExecuteReader(CommandBehavior.SingleRow);

            tokenReader.Read();

            SqlString filePathName = tokenReader.GetSqlString(0);

            SqlBinary fileToken = tokenReader.GetSqlBinary(1);

            tokenReader.Close();

            SqlFileStream sqlFile = new SqlFileStream(filePathName.Value, fileToken.Value, System.IO.FileAccess.ReadWrite);
            sqlFile.Close();

            objSqlTran.Rollback();
            //objSqlTran.Commit();
            con.Close();

        }
    }
    finally
    {
        impersonatedUser.Undo();
    }
}
};

然而,当它到达这条线时:

SqlFileStream sqlFile = new SqlFileStream(filePathName.Value, fileToken.Value, System.IO.FileAccess.ReadWrite);

我得到:

在执行用户定义的例程或聚合“sp_fileController”期间发生 .NET Framework 错误:

System.ComponentModel.Win32Exception: The request is not supported
System.ComponentModel.Win32Exception: 
   at System.Data.SqlTypes.SqlFileStream.OpenSqlFileStream(String path, Byte[] transactionContext, FileAccess access, FileOptions options, Int64 allocationSize)
   at System.Data.SqlTypes.SqlFileStream..ctor(String path, Byte[] transactionContext, FileAccess access, FileOptions options, Int64 allocationSize)
   at System.Data.SqlTypes.SqlFileStream..ctor(String path, Byte[] transactionContext, FileAccess access)
   at StoredProcedures.sp_fileController(String friendlyName, String filePath)

谁能告诉我如何解决这个问题?只是我不能用 sql 2008 express edition 以这种方式执行代码吗?

4

2 回答 2

1

我想我在这里找到了可行的解决方案:

https://social.msdn.microsoft.com/Forums/sqlserver/en-US/f49def09-3b47-4e54-8a53-2dd47762821e/filestream-on-windows-server-2012-the-request-is-not-supported?论坛=sql数据库引擎

总结一下:添加注册表项解决了 SQL Server 11.0.7001 上的问题:

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters\FsctlAllowlist]
"FSCTL_SQL_FILESTREAM_FETCH_OLD_CONTENT"=dword:0x00092560
于 2018-05-11T12:41:07.943 回答
0

正如您在Microsoft Connect 问题 768308中所读到的那样,Microsoft故意阻止在 SQL CLR 程序集中使用SqlFileStream类(即使您授予EXTERNAL_ACCESS或声明程序集为UNSAFE),这听起来很奇怪。

但是,您可以通过 SqlBytes 类型将 FILESTREAM 作为流访问(在博客文章中找到了一个非常好的提示)。至少对于只读用途,我从未尝试过编写。

我复制过去的代码以防博客消失(在一个稍微改进的版本中,正确处理了对象):

using System;
using System.IO;
using System.Data.SqlTypes;
using Microsoft.SqlServer.Server;
using System.Security.Cryptography;

public partial class UserDefinedFunctions
{
    [Microsoft.SqlServer.Server.SqlFunction(DataAccess = DataAccessKind.None, IsDeterministic = true, SystemDataAccess = SystemDataAccessKind.None)]
    public static SqlBinary Hash(SqlBytes source, SqlString hashAlgorithmName)
    {
        if (Source.IsNull) 
        {
            return null;
        }

        using (HashAlgorithm ha = GetHashAlgotithm(hashAlgorithmName.Value)) 
        using (Stream stream = Source.Stream) 
        {
            return new SqlBinary(ha.ComputeHash(source.Stream));
        }
    }
}

我可以确认这绝对适用于只读访问。我从未尝试过写入访问(我正在从外部 C# Windows 服务或 Web 应用程序写入 FILESTREAM 数据)。

于 2014-09-17T14:41:18.923 回答