google app engine - Are single-entity datastore writes atomic? -


in appengine datastore, given entity a = mymodel(a=1, b=2), a.put() atomic? is, if run:

a.a=3 a.b=4 a.put()

am guaranteed entity updated correctly properties, (assuming a.put() did not raise exception, is)?

dan sanderson's book says it is, couldn't find concrete documentation on subject elsewhere.

yes, single entity's update atomic.

as noted in article, given entity single protocol buffer in bigtable row. protocol buffers written atomically.


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