title: objectify v6 - NOT and IN filters no longer supported? Alternatives?
body: <p>The objectify v6 docs say:</p>
  
  <blockquote>
    <p>NOT and IN filters are not supported by the new SDK. You will get a
    runtime error if you try to
    ofy().load().type(Thing.class).filter("field !=", value) or
    filter("field IN" values).</p>
  </blockquote>
  
  <p>Even if in objectify v5, should we stay away from using NOT or IN filters as they are, it looks like, on the way out? </p>
  
  <p>Is there anymore information on why these are no longer supported? Any alternative methods to maybe achieve a similar type of query? Specifically, the IN query. Which is/was pretty useful if you have say a list of user id's that you need to query all of something of.</p>