You can use STRONG consistency on HR and if you get by key then that should work with what you describe. There was just a discussion on this and you can see a related post by Ikai which may also help you from a reply of his to this other discussion: https://groups.google.com/forum/#!searchin/google-appengine/ikai$20eventually$20consistent/google-appengine/<https://groups.google.com/forum/#!searchin/google-appengine/ikai$20eventually$20consistent/google-appengine/X8O2pDZt5i8/NrG3JOkjTUsJ> X8O2pDZt5i8/NrG3JOkjTUsJ<https://groups.google.com/forum/#!searchin/google-appengine/ikai$20eventually$20consistent/google-appengine/X8O2pDZt5i8/NrG3JOkjTUsJ>
Stephen On Sun, Jul 10, 2011 at 9:33 AM, bejayoharen <[email protected]> wrote: > I am designing an app that may not work well with the eventual > consistency model provided by the HR database, and thought someone > could provide some advice. Here is a typical situation: > > 1. Client A requests storage of data identified by KEY on GAE. > 2. the GAE app stores the data; and acknowledges the storage to Client > A. > 3. Client A tells Client B (via another communication protocol) to > fetch data identified by KEY. > 4. Client B asks GAE for the data identified by KEY. > > Unfortunately, with eventual consistency, step 4 may fail. Caching > won't help because 1. caching is not 100% reliable and 2. client A and > client B may be talking to different nodes with different caches. > Worse than this is a situation where instead of storing the data, > client A is updating and client B gets stale data. > > Is there some solution to this, or do I need to use the MS database? > If that's the case, I noticed that in some places, the MS database is > marked as "legacy", which has me worried. > > thanks > > bjorn > > -- > 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. > > -- 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.
