On Fri, Jul 10, 2009 at 2:04 PM, neil souza<[email protected]> wrote: > > the problem: > > how to best structure the id system for a social network app on app > engine. > > > the run down: > > users access the app through a social network. they identify > themselves to the app with a 'platform type id' (pl_type_id, enum) and > 'platform user id' (pl_user_id, 64bit int) pair. examples: user 12345 > at facebook, user 45678 at myspace, etc. > > we need to be able to find their data using that pair. we also need to > be able to find their friend's data using lists of the same sort of > pairs. > > let's say for the sake of simplicity that each user has a User object > in the datastore. we need to be able to efficiently fetch a specific > User object using a (pl_type_id, pl_user_id) pair, and fetch a list of > User objects (up to say 1000) using a list of (pl_type_id, pl_user_id) > pairs. > > > ideas thus far: > > 1.) User has integer properties for pl_user_id and pl_type_id. > resolving one user object is no issue, resolving many requires an 'IN' > query, which is not viable since it makes 1 query for each pair in the > list - NO GOOD > > 2.) User objects use key names of the form '<pl_type_id>:<pl_user_id>' > or something similar. then we can form the key from the provided info > and fetch based on keys. we never used to do this because sql sucked > at finding strings - not sure how app engine does..? - BETTER..?
This is your best option. Datastore gets are a _lot_ faster than datastore queries, and you can fetch multiple IDs in the same operation. -Nick Johnson > > 3.) is there a way to specify the id on a newly created Model? we know > the pl_user_id is unique. we can then have a Model for each network > and build keys from the pl_user_id. this is how we used to roll in the > mysql world. - MAYBE..? > > additional ideas and feedback appreciated, thanks in advance. > > > -- Nick Johnson, App Engine Developer Programs Engineer Google Ireland Ltd. :: Registered in Dublin, Ireland, Registration Number: 368047 --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en -~----------~----~----~----~------~----~------~--~---
