One DAO class for access a database in SQL server, MySQL and MongoDB

Is there a way to create one DAO class like EmployeeDAO and this class should be able to work with SQL Server, MySql and MongoDB. It should somehow change and work with MySqlConnection/SqlConnection and MySqlCommand/SqlCommand. Right now, I have to create three classses for each database. Are there any interfaces that I can use? I could not find any. Thank you.

public abstract class DaoFactory
{
  public static DaoFactory GetInstance(DaoConnection daoConnection)
    {
        DaoFactory instance = null;

        switch (daoConnection)
        {
                case DaoConnection.Default:
                case DaoConnection.MySQL:
            {
                instance = new MySqlConnectionFactory(MySqlServer, MySqlPort, MySqlUser, MySqlPassword);
                break;
            }
        }

        return instance;
    }

 protected string ConnectionString { get; set; }

 public abstract DbConnection GetConnection();

}

public class MySqlConnectionFactory : DaoFactory
{
    public MySqlConnectionFactory(string server, string port, string user, string password) : base(server, port, user, password)
    {
        this.ConnectionString = string.Format("Server={0}; Port={1} Uid={2}; Pwd={3}; pooling=true", server, port, user, password);
    }

    public override DbConnection GetConnection()
    {
        return new MySqlConnection(this.ConnectionString);
    }
}


public class EmployeeDao : IEmployeeDao
{
    private const string InsertEmployee = "INSERT INTO employees VALUES (@name,@age)";

    private DaoFactory daoFactory;

    EmployeeDao(DaoFactory daoFactory)
    {
        this.daoFactory = daoFactory;
    }

    public void Insert(Employee employee)
    {
        MySqlConnection connection =  (MySqlConnection) this.daoFactory.GetConnection();

        using (connection)
        {
            var commannd = new MySqlCommand(InsertEmployee, connection);
            commannd.ExecuteNonQuery();

        }
    }