I have a XML file and I'm populating a HTML table with the data in the XML using jQuery. The XML file has the following format:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>

1. <Root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

   <Row>

       <Patologia>Alzheimer</Patologia>

       <Molecula>Galantamina</Molecula>

       <Nombre_Comercial>RAZADYNE®</Nombre_Comercial>

       <Fecha_Exp>2017-06</Fecha_Exp>

       <Propietario>JANSSEN PHARMS</Propietario>

   </Row>

   <Row>

       <Patologia>Alzheimer</Patologia>

       <Molecula>Liraglutida</Molecula>

       <Nombre_Comercial>Victoza®</Nombre_Comercial>

       <Propietario>NOVO NORDISK INC</Propietario>

   </Row>

   <Row>

       <Patologia>Alzheimer</Patologia>

       <Nombre_Comercial>ARICEPT ODT®</Nombre_Comercial>

       <Fecha_Exp>2018-03</Fecha_Exp>

       <Propietario>EISAI INC</Propietario>

   </Row>

I have the following JavaScript:

function showData() {

1.     $.ajax({

           type: "GET",

           url: "test2.xml",

           dataType: "xml",

           success: function (xml) {

               $('#mainTable').empty();

               var fila = $(xml).find("Row");

               var tabla = $("#mainTable");

   
   

               var row = $(tabla[0].insertRow(-1));

   
   

               fila.eq(0).children().each(function () {

                   var headerCell = $("<th />");

                   headerCell.html(this.nodeName);

                   row.append(headerCell);

               });

   
   

               $(fila).each(function () {

                   row = $(tabla[0].insertRow(-1));

                   $(this).children().each(function () {

                       var cell = $("<td />");

                       cell.html($(this).text());

                       row.append(cell);

                   });

               });

   
   

               var thead = tabla.find("thead");

               var thRows = tabla.find("tr:has(th)");

   
   

               thead = $("<thead />").prependTo(tabla);

   
   

               var copy = thRows.clone(true).appendTo("thead");

               thRows.remove();

   
   

               $("#mainTable td:empty").append("epale");

           }

       });

   }

The problem that I'm having is that in the XML file some rows are missing a column or two. When filling the table using the jQuery code it messes up the columns when a column is missing from the XML. How can I add an empty cell when a column is missing from the xml? 

I hope I was able to explain the issue.

Any help would be greatly appreciated.