using (OleDbCommand Update = new OleDbCommand(
                 "UPDATE [BoardDetail] SET BoardImage= '(?)' WHERE BoardID='" + oItem.BoardID + "' AND BoardSerialNo='" + oItem.BoardSerialNo + "' ", connection))
             {
                 OleDbParameter imageParameter =
                 Update.Parameters.Add("@image", OleDbType.Binary);
                 imageParameter.Value = content;
                 imageParameter.Size = content.Length;
                 Update.ExecuteNonQuery();
             }

SET BoardImage= '(?)'

SET BoardImage= @image