怎么向ORACLE库中存入二进制的图片,我这样写为什么不对,请高手指点

byte[] buff= new byte[fileLength];
Stream streamobj = ufile.InputStream;
streamobj.Read(buff,0,fileLength);
OracleConnection conn=new OracleConnection(getConnectString());
OracleCommand comm=new OracleCommand();
comm.Connection=conn;
comm.CommandText="insert into PICTURE(PICTUREID,PICTUREDATA,ftype,ERP_CODE,forder) values(@fid,@fphoto,@ftype,@erp_code,@forder)";
comm.Parameters.Add("@fid",SqlDbType.Char);
comm.Parameters.Add("@fphoto",SqlDbType.Image);
comm.Parameters.Add("@ftype",SqlDbType.Char);
comm.Parameters.Add("@erp_code",SqlDbType.Char);
comm.Parameters.Add("@forder",SqlDbType.Char);
comm.Parameters["@fid"].Value=Guid.NewGuid().ToString();
comm.Parameters["@ftype"].Value=this.Request["type"].ToString();
comm.Parameters["@forder"].Value=this.forderid.Text;
comm.Parameters["@fphoto"].Value=buff;
comm.Parameters["@erp_code"].Value=this.Request["erpCode"].ToString();try
{
conn.Open();
comm.ExecuteNonQuery();

}
catch(Exception ex)
{
throw ex;
}
finally
{
          conn.Close();
}错误提示为:非法的变量名/编号请问如何存图片成二进制,注意是ORACLE库!!!!