连续运行MySQL查询(在c#程序中)以查找新添加的记录

我有一个用c#编写的程序，该程序接受MySQL查询的结果集，并将列值转换为webrequest中HTML字符串的一部分。它工作得很好，但我需要能够连续运行这个程序，只抓取以前没有抓取的记录，这样我就不会一遍又一遍地发送相同的数据。有办法做到这一点在MySQL/c# ?我正在使用的查询没有时间戳。

编辑:代码:

public class mysqlExporter
{
    public mysqlExporter()
    {
        //Create MySQL connection
        string SQLString;
        SQLString = "my connection string";
        MySqlConnection conn = new MySqlConnection(SQLString);
        //Write Query
        MySqlDataAdapter eQuery = new MySqlDataAdapter(@"SELECT * FROM whatever;", conn);
        //Put SQL results into dataset
        DataSet eExport = new DataSet();
        eQuery.FillSchema(eExport, SchemaType.Source);
        eQuery.Fill(eExport);
        //Convert dataset to datatable
        DataTable exportTable;
        exportTable = eExport.Tables[0];
        //Make a webrequest for each record
        foreach (DataRow row in exportTable.Rows)
        {
            //Push each record out
            WebRequest httpPost = WebRequest.Create("http://whatever.whatever/name="+row["name"]+"&phone="+row["phone"]);
            httpPost.Method = "POST";
            string postData = httpPost.ToString();
            byte[] byteArray = Encoding.UTF8.GetBytes(postData);
            httpPost.ContentLength = postData.Length;
            Stream dataStream = httpPost.GetRequestStream();
            dataStream.Write(byteArray, 0, byteArray.Length);
            dataStream.Close();
            WebResponse response = httpPost.GetResponse();
            Console.WriteLine(((HttpWebResponse)response).StatusDescription);
            dataStream = response.GetResponseStream();
            StreamReader reader = new StreamReader(dataStream);
            string responseFromServer = reader.ReadToEnd();
            reader.Close();
            dataStream.Close();
            response.Close();
        }
    } 
}