title: How to properly handle mongoose schema migrations?
body: <p>I'm completely new to MongoDB &amp; Mongoose and can't seem to find an answer as to how to handle migrations when a schema changes.</p>
  
  <p>I'm used to running migration SQL scripts that alter table structure and any underlying data that needs to be changed. This typically involves DB downtime.</p>
  
  <p>How is this typically handled within MongoDB/Mongoose? Any gotcha's that I need to be aware of?</p>