After a sleepless night and run over the StackOverflow I could not find the method (function) that can resolve my problem.

What I wrote is very harder for the server. Is there any more clever way to resolve this problem?

Here my code:

public static int GetIndexLong(string TblName) 
{ 
    int rowsNbr = 0; 
    using(MySqlConnection conn = new MySqlConnection(PublicVariables.cs)) 
    { 
        using(MySqlCommand cmd = new MySqlCommand("SELECT * FROM " + TblName, conn)) 
        { 
            conn.Open(); 
            using (MySqlDataReader reader = cmd.ExecuteReader()) 
            { 
                while (reader.Read()) 
                { 
                    ++rowsNbr; 
                } 
            } 
            return rowsNbr; 
        } 
    } 
}

It does the job but I know it's not the good way.

Working with C# Express 2008 on .NET 4.0.