title: how to skip null values in odata response?
body: <p>I have an odata web service that is returning some null values. I would like to skip these null values. 
  I tried to use the Ne(Not equal) operator to filter the data with null values:</p>
  
  <pre><code>analyticView.xsodata/analyticView?$select=QUANTITY_SOLD,SALE_PRICE&amp;$filter=SALE_PRICE+Ne+null)&amp;$format=json
  </code></pre>
  
  <p>and I am getting the following error message: </p>
  
  <pre><code>"Illegal operation 'Ne' at position 11."
  </code></pre>
  
  <p>I tried also to combine the Not operator with the eq operator in this way:  </p>
  
  <pre><code>analyticView.xsodata/analyticView?$select=QUANTITY_SOLD,SALE_PRICE&amp;$filter=not(SALE_PRICE+eq+null)&amp;$format=json
  </code></pre>
  
  <p>I keep getting an error message saying: </p>
  
  <pre><code>value: "No property 'null' exists in type ...
  </code></pre>
  
  <p>I am using SAP HANA analytic view as a data source, but I thing the issue is not vendor dependent. 
  so, what to do to skip the null values? </p>