private string MakeFilteredQueryDContr(Dictionary<string, List<DateTime>> searchedTable)
        {
            string filter = string.Empty;

            if (searchedTable == null)
                return filter;

            foreach (KeyValuePair<string, List<DateTime>> kvp in searchedTable)
            {
                if (kvp.Value == null /*|| kvp.Value*/)
                    continue;
                foreach (DateTime dcontr in kvp.Value)
                {
                    filter += string.Format(" SELECT '{0}' from '{1}' where '{2}'", kvp.Key,
                        archiveDataSet.Tables["workcontract"], dcontr);
                }
            }           
            
            return filter;
        }