/// <summary>
        /// gets from any record the user_id, who has deleted it - if it has not 0 here
        /// </summary>
        /// <param name="indexOfUser">index of spec. record</param>
        /// <returns>the name of the user, who deleted</returns>
        public string getWhoModifiedRecord(int indexOfUser)
        {
            string userName = "";

            string[] result;
            try
            {
                parameters = new List <KeyValuePair <string, string> >();
                KeyValuePair <string, string> userId = new KeyValuePair <string, string>("@userId", indexOfUser.ToString());
                parameters.Add(userId);
                mdi.openConnection();
                result = mdi.execPrepQueryOneRowInStringArrWithKVPList(queryWhoChangedTheRecord, parameters, 1);
                mdi.closeConnection();
            }
            catch (Exception e)
            {
                mdi.closeConnection();
                throw new ErrorServiceWhoModified("A rekord törlője kereséséhez kérés megalkotása sikertelen (ModProdListQual) "
                                                  + e.Message);
            }
            if (result == null)
            {
                throw new ErrorServiceWhoModified("A rekord módosítójának visszakeresése sikertelen (ModProdListQual)");
            }
            foreach (string s in result)
            {
                userName += s + " ";
            }
            return(userName);
        }