Fetching ColumnNames on Basis of Value in MySql C#

Steps:-
       string sql = "select * from <tablename> where <columnName="Yes">";  //Query to MySql.
     
        objDB.GetData(sql,ref tbl_Services); // Get Data in tbl_services table.
     
        //Fetching ColumnNames on Basis of Value(Yes) in a List Control:-

        List<string> columnNames = new List<string>();  // List control initialization.
        if (tbl_Services.Rows.Count > 0)
        {
            foreach (DataColumn dc in tbl_Services.Columns)
            {
                if (tbl_Services.Rows[0][dc.ColumnName].ToString() == "Yes")
                {
                    columnNames.Add(dc.ColumnName);    // Required Data will be stored in ColumnNames List
                }
            }
        }