Placement of sorted entry in Google App Engine Datastore

Question

I'd like to determine what place a particular entry is in, but the appropriate GQL query is escaping me. Ideally I'd like to know the following details, which seem like they should be known by the Datastore. I just can't seem to figure how to determine it. Can someone help?

• the placement of a particular entry (in a given sorting, i.e. by a particular property)
• the total number of entries that exist (w/o retrieving them, just the count)
• the next entry in the list (I figure as long as I can get the placement, I can make the right query to get the next one by simply getting 2 and taking the latter)

Can someone help?

Answer 1

If you're using Python, check out the google-app-engine-ranklist project, which implements a rank list in the App Engine datastore.