什么是ZRangeValid意味着什么

Question

此代码用于读取excel文件，ZRangeValid的含义是什么，rs.fields（0）.value是指什么？请解释我的两个问题

 var strConnString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + strXLPath + ";Extended Properties=\"Excel 12.0;HDR=YES;\";";

        var conn = new ActiveXObject("ADODB.Connection");


        conn.open(strConnString, "", "");

        var rs = new ActiveXObject("ADODB.Recordset");

        var rsrowCount = new ActiveXObject("ADODB.Recordset");
        rs = conn.execute("select * from ZRangeValid");
        if (rs.fields(0).value != 'YES') {
            alert(strXLPath + " requested numbers spreadsheet is not valid.\nPlease validate the spreadsheet data and retry.")
            rs = null;
            rsSheet = null;
            conn.close();
            conn = null;
            return false

        }