MySqlCommand cmd = con.CreateCommand();
cmd.CommandText = @"INSERT INTO dict (pre, dist, dict.char, score) VALUES(@pre, @dist, @char, @score) ON DUPLICATE KEY UPDATE score = score + @score";
cmd.Parameters.Add("@pre", MySqlDbType.VarChar, 32);
cmd.Parameters.Add("@dist", MySqlDbType.Int32);
cmd.Parameters.Add("@char", MySqlDbType.VarChar, 1);
cmd.Parameters.Add("@score", MySqlDbType.Double);
cmd.Prepare();

cmd.Parameters[3].Value = score;

Console.WriteLine(cmd.IsPrepared);
cmd.ExecuteNonQuery();

using (MySqlConnection con = new MySqlConnection(@"SERVER=localhost;DATABASE=rb;UID=;PASSWORD=;"))
        {
            con.Open();

            using (MySqlCommand cmd = con.CreateCommand())
            {
                cmd.CommandText = @"INSERT INTO test (test.test) VALUES(?asdf)";
                cmd.Prepare(); //doesn't work

                cmd.Parameters.AddWithValue("?asdf", 1);

                cmd.ExecuteNonQuery();
            }
        }