SqlConnection conn =null;

　　SqlCommand cmd = null;

　　SqlParameter param = null;

　　FileStream fs = null;

　　const string sConn = "server=(local);Initial

　　Catalog=Northwind;UID=ctester;PWD=password";

　　try {

        conn = new SqlConnection(sConn);

        cmd = new SqlCommand("UPDATE Categories SET Picture = ?Picture WHERE

        CategoryName = 'Seafood'", conn);

        fs = new FileStream("c:\\Builder.doc", FileMode.Open, FileAccess.Read);

        Byte[] blob = new Byte[fs.Length];

        fs.Read(blob, 0, blob.Length);

        fs.Close();

        param = new SqlParameter("Picture", SqlDbType.VarBinary, blob.Length,

        ParameterDirection.Input, false, 0, 0, null, DataRowVersion.Current, blob);

        cmd.Parameters.Add(param);

        conn.Open();

        cmd.ExecuteNonQuery();

　　} catch (SqlException e){

　　    Console.Write("SQL Exception: " + e.Message());

　　} catch (Exception e) {

　　    Console.Write("Exception: " e.Message());

　　}

cmd = new SqlCommand("UPDATE Categories SET Picture =@Picture Picture WHERE


new SqlParameter("Picture", byte[])

------解决方案--------------------

SqlConnection conn =null;//连接字符串来用的

　　SqlCommand cmd = null; //执行SQL语句

　　SqlParameter param = null;//传参数来用的

　　FileStream fs = null;//文件流

　　const string sConn = "server=(local);Initial

　　Catalog=Northwind;UID=ctester;PWD=password";//SQL的连接字符串

　　try {

       conn = new SqlConnection(sConn);//实利化连接字符串

       cmd = new SqlCommand("UPDATE Categories SET Picture = ?Picture WHERE

       CategoryName = 'Seafood'", conn);//SQL语句

       fs = new FileStream("c:\\Builder.doc", FileMode.Open, FileAccess.Read);//用文件流读取c:\\Builder.doc

       Byte[] blob = new Byte[fs.Length];//一个Byte数组

       fs.Read(blob, 0, blob.Length);//读取文件流

       fs.Close();//关闭文件流

       param = new SqlParameter("Picture", SqlDbType.VarBinary, blob.Length,

       ParameterDirection.Input, false, 0, 0, null, DataRowVersion.Current, blob);//传入的参数

       cmd.Parameters.Add(param);//添加到数据库里面

       conn.Open();//关闭数据库连接

       cmd.ExecuteNonQuery();//反回受影响行数

　　} catch (SqlException e){

　　    Console.Write("SQL Exception: " + e.Message());//异常

　　} catch (Exception e) {

　　    Console.Write("Exception: " e.Message());//异常

　　}


------解决方案--------------------
MySQL/MSSQL?
如果文件比较大的话，需要循环读取文件内容，。
MSSQL下面是：
UPDATETEXT { table_name.dest_column_name dest_text_ptr }
   { NULL | insert_offset }
    { NULL | delete_length }
    [ WITH LOG ]
    [ inserted_data
   | { table_name.src_column_name src_text_ptr } ]

如果2005等较新的版本，用write 子 句的update.
USE AdventureWorks;
GO
DECLARE @MyTableVar table (
   DocumentID int NOT NULL,
   SummaryBefore nvarchar(max),
   SummaryAfter nvarchar(max));
UPDATE Production.Document
SET DocumentSummary .WRITE (N'features',28,10)
OUTPUT INSERTED.DocumentID,
      DELETED.DocumentSummary,  
      INSERTED.DocumentSummary  
   INTO @MyTableVar
WHERE DocumentID = 3 ;
SELECT DocumentID, SummaryBefore, SummaryAfter  
FROM @MyTableVar;
GO