// Procède à l'importation des joueurs.
        private void LoadPlayers()
        {
            string query = "select * from players";

            using (DataTableReader reader = SqlTools.ExecuteReader(query))
            {
                while (reader.Read())
                {
                    // Calcul de la latéralité.
                    string hand         = reader.GetString("hand");
                    bool?  isLeftHanded = null;
                    if (!string.IsNullOrWhiteSpace(hand))
                    {
                        isLeftHanded = hand.Trim().ToUpper() == "L";
                    }

                    new Player(reader.GetUint64("ID"),
                               reader.GetString("name"),
                               reader.GetString("nationality"),
                               isLeftHanded,
                               reader.GetUint32Null("height"),
                               reader.GetDateTimeNull("date_of_birth"),
                               reader.GetDateTimeNull("date_begin"),
                               reader.GetDateTimeNull("date_end"));

                    _dataLoadingProgressEventHandler?.Invoke(new DataLoadingProgressEvent(100 * ++_currentDataCount / _totalDataCount));
                }
            }

            // Importation de l'historique des nationalités.
            query = "select * from players_nat_history order by date_end";
            using (DataTableReader reader = SqlTools.ExecuteReader(query))
            {
                while (reader.Read())
                {
                    Player.AddNationalitiesHistoryEntry(reader.GetUint64("ID"), reader.GetString("nationality"), reader.GetDateTime("date_end"));

                    _dataLoadingProgressEventHandler?.Invoke(new DataLoadingProgressEvent(100 * ++_currentDataCount / _totalDataCount));
                }
            }
        }