Thanks Barry. That is indeed what we have done so far. But this scenario is different and we need to make the update.
For what you are suggesting, we have to change the code in many different locations to catch the missing property and update. In some of these places, we may not be even in a position to make the update! Another problem could be that if I am accessing 100s of elements, and I have to update them all, it could lead to slow response for the activity and may even exceed 60s limit. Also, if we are not re-writing those elements inside our code, then we will have to bear the same cost as with my method? You are assuming we will write the element anyway and hence defray the cost. Bottom line is, even if we had to write those 1600 numbers, why should it cost 5.8 million OPs? If we signup 1600 users in a day, each with one entry in the DB, then we'll use up all our quota! Regards, Sarang On Thursday, July 5, 2012 6:23:49 PM UTC+5:30, barryhunter wrote: > > > > On Thu, Jul 5, 2012 at 1:40 PM, Sarang <sar...@mycontactid.net> wrote: > > >> tell us what is the "right" way to make such changes? >> > > Well the datastore is in general 'schemaless' - so you should be able to > *avoid* having to make such changes. > > It doesnt matter that some entities have a different schema to others. > Drop the SQL mindset ;) > > > So you just add the extra field, the next time you happen to modify that > particular entity anyway. So the 'migration' happens, very slowly over > time. Costs very little extra, because the write would of happened anyway. > > > Each entity could have a 'version' value, which the code notes is > 'outdated' and then updates it automatically. > > > -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To view this discussion on the web visit https://groups.google.com/d/msg/google-appengine/-/jMq4CRzcsjsJ. To post to this group, send email to google-appengine@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
