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Try this: SELECT * FROM PreparedTransaction WHERE __key__=KEY('agdwYXllbGV4cjkLEhNQcmVwYXJlZFRyYW5zYWN0aW9uIiAwMDAwMGNjMjMwYzg2MTFjZTFhOWZjZDJkZDEzMWMyNww') This is documented here: http://code.google.com/appengine/docs/python/datastore/gqlreference.html

One thing you get used to on appengine is that any bulk data work requires the task queue.  You can use a little bit of framework and make all of these transforms (including deleting data) a question of just writing a simple task class and firing it off.  You'll want a copy of the Deferred servlet: http://code.google.com/p/gaevfs/source/browse/trunk/src/com/newatlant... Fair warning:  I found that I needed to change the code to make it perform base64 encoding all the time, not just on the dev instance.

One thing you get used to on appengine is that any bulk data work requires the task queue.  You can use a little bit of framework and make all of these transforms (including deleting data) a question of just writing a simple task class and firing it off.  You'll want a copy of the Deferred servlet: http://code.google.com/p/gaevfs/source/browse/trunk/src/com/newatlant... Fair warning:  I found that I needed to change the code to make it perform base64 encoding all the time, not just on the dev instance.

What do I mean by life cycle events? Events like entity creation, entity update and entity deletion. Mainstream ORM systems popularised callbacks like oncreate, onupdate, ondelete. Introducing such callbacks in the Java and Python APIs may be easy, but things get messy when you consider the ecosystem of alternative language implementations based on the Java API: developers using alternative languages would be forced to use Java to write the callbacks. There is a more robust solution though. Google App Engine already leverages the power of webhooks in such APIs as taskqueue, email, xmpp and more. Webhooks can elegantly solve the life cycle management problem as well: when an entity is created, updated or deleted through the Datastore viewer a corresponding webhook is triggered. Let's say the user is playing with Article entities, the webhooks uris could be: http://myapp.com/_ah/admin/datastore/le/Article/create/{key} http://myapp.com/_ah/admin/datastore/le/Article/update/{key} http://myapp.com/_ah/admin/datastore/le/Article/delete/{key} Slightly more work than callbacks, but still simple and effective. If there is an even better solution, I would love to hear about it in the comments section.