Google App Engine - Dealing with concurrency issues in storing an object

Posted by Spines on Stack Overflow See other posts from Stack Overflow or by Spines
Published on 2010-04-08T20:58:38Z Indexed on 2010/04/08 21:03 UTC
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google-app-engine

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concurrency

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google-datastore

My User object that I want to create and store in the datastore has an email, and a username. How do I make sure when creating my User object that another User object doesn't also have either the same email or the same username?

If I just do a query to see if any other users have already used the username or the email, then there could be a race condition.

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