No, get-by-key that reaches the datastore is a Read Operation. However, memcache hits are free.
Jeff On Fri, Apr 20, 2012 at 1:56 AM, Peter Han <[email protected]> wrote: > "However, you can convert queries into keys-only queries followed by > batch get()s; this will cost small datastore operations for cache > hits > rather than full read operations" > > keys-only query is a small datastore operation thats is clear, but > batch get of entities by key also? Thank you. > > > > > > On Apr 18, 6:49 pm, Jeff Schnitzer <[email protected]> wrote: >> On Wed, Apr 18, 2012 at 3:36 AM, cloudpre <[email protected]> wrote: >> > Jeff - thanks for the note. I have been trying to add few items in >> > memcache manually. >> >> > Can put operations also be saved? Let's say I am updating the same >> > query again after few seconds. >> >> I'm not sure what you mean here. The cache covers get(), put(), and >> delete() operations. Queries do not affect the cache at all. >> However, you can convert queries into keys-only queries followed by >> batch get()s; this will cost small datastore operations for cache hits >> rather than full read operations. Objectify4 will actually do this >> for you. >> >> > Does it work flawlessly in the production? The last thing I want to >> > see is our thousands of customers coming back and complaining. >> >> There have not been any complaints for the current cache code (3.1+), >> and it is fairly widely used. Older versions of the cache code (3.0 >> and prior) had synchronization issues, but for 3.1 I rewrote it with >> some help from Ari and Alfred (Google). It should be transactionally >> safe - even under heavy contention - as long as you don't hit >> DeadlineExceededExceptions. >> >> Jeff > > -- > 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.
