title: Get all of a collection's documents id's RavenDB for a "per-document" modification
body: <p>I'm currently trying to update my documents in a ravendb DB. The issue is that i have a method that updates one document, yet it takes as a parameter the id of the doc.
  I'm using python, therefore : pyravenDB as an interface.</p>
  
  <p>The method is the following :</p>
  
  <pre><code>def updateDocument(self,id,newAttribute)
  
          with self.store.open_session() as session:
              doc = session.load(id)
              doc.newAttribute= newAttribute
              session.save_changes()
  </code></pre>
  
  <p>My idea is the i will use a simple for loop with all the id's of the targeted collection and call the updateDocument method.</p>
  
  <p>I think there is an updatebyindex method, but I don't get how to adapt it to my usecase.</p>
  
  <p>How can I obtain this ?</p>
  
  <p>Thanks !</p>