How to Read MySql string data into a form of list<string>

See more:

MySQL

C#4.0

hi guys what im trying to do here is to read a data(string) coming from my MySql Database but in a form of List<string> for a faster processing and to save memory.

public void GetFace(string name)
        {
            
            using (var Connection = new MySqlConnection(connectionString))
            {
                Connection.Open();
                try
                {
                    using (MySqlCommand selectcommand = Connection.CreateCommand())
                    {
                        selectcommand.CommandText = "select columnname from tablename";
                        using (MySqlDataReader reader = selectcommand.ExecuteReader())
                        {
                            var Names_list = new List<string>();
                            while (reader.Read())
                            {
                                Names_list.Add(name);
                                Attendance(Names_list.ToArray()); // it is a method which has a string[] paramater
                            }
                        }
                    }
                }
                catch (Exception ex)
                {
                    ex.Message.ToString();
                }
            }
        }

but as I reload the database there is seem to be no changes.
Attendance method is a method that updates the database:
here is the Attendance method:

private void Attendance(string[] name)
        {
            
            using (var Connection = new MySqlConnection(connectionString))
            {
                Connection.Open();
                try
                {
                    DateTime CurrentDate;
                    CurrentDate = DateTime.Now;
                    using (MySqlCommand selectcommand = Connection.CreateCommand())
                    {
                        selectcommand.CommandText = "UPDATE tablename SET " + CurrentDate.ToString("MM_dd_yyyy") + " = '" + CurrentDate + "' WHERE columnname = '" + name + "'";
                        selectcommand.ExecuteNonQuery();
                    }
                }
                catch (Exception ex)
                {
                    ex.Message.ToString();
                }
            }
        }

thank you for your answer