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In Java you can use Query cursors to [1] limit your results.  As far as aggregate functions (like MIN and MAX) you can use [2] indexes to achieve the similar result (ie. order by age and get the top result) [1] http://code.google.com/appengine/docs/java/datastore/queriesandindexe... <http://code.google.com/appengine/docs/java/datastore/queriesandindexe...> [2] http://code.google.com/appengine/docs/java/datastore/queriesandindexe... <http://code.google.com/appengine/docs/java/datastore/queriesandindexe...> On Sat, Dec 4, 2010 at 10:31 AM, Jeff Schwartz <jefftschwa...@gmail.com>wrote:

Objectify is a thin wrapper library around the native low level java datastore api. It adds numerous convenience methods but doesn't stray from the low level api. In addition, it allows you to define your models as pojos using java annotations for things like numeric and string key ids, properties which are keys of a parent, etc. I wouldn't think of using anything else. The low level api examples I just gave you map very closely to how you would accomplish the same thing in Objectify. You can read more about Objectify on their wiki at http://code.google.com/p/objectify-appengine/wiki/IntroductionToObjec....

public final class KeyRangeextends java.lang.Objectimplements java.lang.Iterable<Key>, java.io.Serializable Represents a range of unique datastore identifiers from getStart().getId() to getEnd().getId() inclusive. The Keys returned by an instance of this class have been consumed in the datastore's id-space and are guaranteed never to be reused. This class can be used to construct Entities with Keys that have specific id values without fear of the datastore creating new records with those same ids at a later date. This can be helpful as part of a data migration or large bulk upload where you may need to preserve existing ids and relationships between entities. This class is threadsafe but the Iterators returned by iterator() are not.