title: Mongoose: How to handle versioning?
body: <p>Today I came to know about versioning concept in MongooseJS(here <a href="http://aaronheckmann.blogspot.in/2012/06/mongoose-v3-part-1-versioning.html" rel="noreferrer">Mongoose v3 part 1 :: Versioning</a>). But I have question here, I like the versioning feature of Mongoose, but what should I do when my schema changes ? </p>
  
  <p>For example, initially my schema looks like,</p>
  
  <pre><code>{
   "_id": String,
   "title": String,
   "description": String
  }
  </code></pre>
  
  <p>Since I didn't know about versioning, i didn't add any versionKey option, just used the default versionKey, <strong>__v</strong>.</p>
  
  <p>I created few documents with this above schema. Later I modified the schema as,</p>
  
  <pre><code>{
   "_id": String,
   "title": String,
   "description": String,
  
   "comments": Array
  }
  </code></pre>
  
  <p>Here comes the problem, If I create any new document after this schema change I could able to add/push comments to the document.</p>
  
  <p>But If I want to add/push comments to the document which were created with initial schema, I couldn't able to do, it throws <strong>Versioning Error: No matching document found</strong>. </p>
  
  <p>Is there anyway to overcome this problem without disabling or skipping the versioning ?</p>