/// <summary>
        /// This method add news ngrams or update if already exists the same ngram in database.
        /// </summary>
        /// <param name="tableName">Name of table.</param>
        /// <param name="ngrams">List of ngrams.</param>
        /// <inheritdoc />
        public void AddOrUpdateNgramsToTable(string tableName, List <NGram> ngrams)
        {
            if (ngrams == null || ngrams.Count <= 0)
            {
                return;
            }

            _db.ConnectToDb();
            foreach (var item in ngrams)
            {
                var commandText = _provider.InsertOrUpdateNgramString(item);
                _db.ExecuteNonQueryDb(commandText);
            }
            _db.Disconnect();
        }