title: How do you properly handle null values in DataTables?
body: <p>I'm trying hard to understand the DataTables documentation, and I'm looking for examples, but I just don't get how to handle null values.</p>
  
  <p>In SQL, I send a JSON string back to my JS app.  I discovered I had to use <code>INCLUDE_NULL_VALUES</code> -- so, I'm no longer missing anything in the JSON array/object.</p>
  
  <p>Here's how I'm populating the table.  My <code>ary</code> is an array of objects with data like this:</p>
  
  <pre><code>ary = [{"Effective Date":"2001-07-01","Schedule":"UR-FUPA","Description":"High Up Dude","Calculated":"No","Base Schedule":"","Factor":null}, {...}, {...}]
  
  $("#tblSomeTable").DataTable({
      "data": ary,
      "columns": [
          {
              "data": "Effective Date"
          },
          {
              "data": "Schedule"
          },
          {
              "data": "Description"
          },
          {
              "data": "Calculated"
          },
          {
              "data": "Base Schedule"
          },
          {
              "data": "Factor"
          }
      ],
      "columnDefs": [{
          "targets": _all,
          "defaultContent": ""
      }],
      "paging": false,
      "ordering": true,
      "info": false,
      "searching": false,
  });
  </code></pre>
  
  <p>So, how do I set the default content to an empty string if the cell has no data?</p>
  
  <p>You can see above that I tried to use the "defaultContent" option to target all columns, but that is not working.</p>
  
  <p>I always appreciate your help.  I'm not asking you to do my work, I just need an example I can understand, and your guidance in the right direction.</p>