Hi Ikai, In traditional RDBMS like Oracle, MySQL, there is truncate command to truncate a table. It is very light in term of resource usage.
Do we have similar feature to truncate a kind in datastore? Such a feature would make housekeeping old data a lot more efficient. The lack of such feature would be a major bottleneck that prevents us from moving our serious business apps to App Engine. Regrards, SP On Wednesday, 21 December 2011 02:39:37 UTC+8, Ikai Lan (Google) wrote: > > Guess I forgot about the "EntitiesByKind" index: > > http://code.google.com/appengine/articles/storage_breakdown.html > > Yes, the correct number should be 22 datastore writes. > > -- > Ikai Lan > Developer Programs Engineer, Google App Engine > plus.ikailan.com | twitter.com/ikai > > > > On Tue, Dec 20, 2011 at 4:58 AM, Brian Quinlan <bqui...@google.com > <javascript:>> wrote: > >> I think that Ikai made an off-by-one-error: it requires 22 writes >> assuming that every property is indexed :-) >> >> Check out "Entity Delete (per entity)" at: >> >> http://code.google.com/appengine/docs/billing.html#Billable_Resource_Unit_Cost >> >> Cheers, >> Brian >> >> On Tue, Dec 20, 2011 at 11:47 PM, supercobra <super...@gmail.com >> <javascript:>> wrote: >> > Could you explain (again?) how a deletion of an entity w/ 10- property >> is 21 >> > writes? >> > >> > >> > On Mon, Dec 19, 2011 at 3:18 PM, Ikai Lan (Google) <ika...@google.com >> <javascript:>> >> > wrote: >> >> >> >> One thing you can do is making this really slow. The free quota >> actually >> >> gives you quite a bit of quota (if your app is relatively small) so if >> you >> >> can stretch out your job you can purge a relatively small datastore at >> low >> >> cost. >> >> >> >> I suspect what makes this expensive is datastore ops, not instance >> hours. >> >> Deleting an entity with 10 properties is 21 writes! There's not a lot >> we can >> >> do there ... >> >> >> >> -- >> >> Ikai Lan >> >> Developer Programs Engineer, Google App Engine >> >> plus.ikailan.com | twitter.com/ikai >> >> >> >> >> >> >> >> On Mon, Dec 19, 2011 at 9:50 AM, Patrick Twohig >> >> <pat...@namazustudios.com <javascript:>> wrote: >> >>> >> >>> Hi, >> >>> >> >>> I have a bit of old data that I want to clean out. I tried to write a >> >>> fanout operation to clean out some of the old data, but it's actually >> manged >> >>> to run out my budget in a few hours. I'm curious if there would be a >> way to >> >>> delete huge amounts of old data that isn't needed anymore. Is there >> a tool >> >>> or something that i can use to efficiently purge entity groups from my >> >>> application? Any help would be greatly appreciated. >> >>> >> >>> Thanks, >> >>> Patrick. >> >>> >> >>> -- >> >>> Patrick H. Twohig. >> >>> >> >>> Namazu Studios >> >>> P.O. Box 34161 >> >>> San Diego, CA 92163-4161 >> >>> >> >>> -- >> >>> You received this message because you are subscribed to the Google >> Groups >> >>> "Google App Engine" group. >> >>> To post to this group, send email to google-a...@googlegroups.com >> <javascript:>. >> >>> To unsubscribe from this group, send email to >> >>> google-appengi...@googlegroups.com <javascript:>. >> >>> 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 google-a...@googlegroups.com >> <javascript:>. >> >> To unsubscribe from this group, send email to >> >> google-appengi...@googlegroups.com <javascript:>. >> >> 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 google-a...@googlegroups.com >> <javascript:>. >> > To unsubscribe from this group, send email to >> > google-appengi...@googlegroups.com <javascript:>. >> > 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 google-a...@googlegroups.com >> <javascript:>. >> To unsubscribe from this group, send email to >> google-appengi...@googlegroups.com <javascript:>. >> 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 unsubscribe from this group and stop receiving emails from it, send an email to google-appengine+unsubscr...@googlegroups.com. To post to this group, send email to google-appengine@googlegroups.com. Visit this group at http://groups.google.com/group/google-appengine. For more options, visit https://groups.google.com/d/optout.
