Excuse my english please. I used delete as example because I assume it is the quickest data-operation.
Not that following would change outcome of this thread but... ... I wonder whether IDs are generated by the same %something% in the Datastore that later writes the data. Or whether it might look like this: > my code > > Objectify/JDO ... ... > > > > > Datastore - ?ID generator? <- maybe this is where allocateIds() gets its response from > > > > > > Datastore - Writer <- CRUD go here I imagine there might be kind of 'memcache' above the Datastore itself... On Tue, Aug 10, 2010 at 1:05 PM, Jeff Schwartz <[email protected]>wrote: > I am not sure exactly what you mean when you say "allocation does not go > the whole way to the very Datastore." Batch puts return a list of keys > associated with the items that were saved to the datastore. Deletes are > quick because they are done by key and there is no serialization required > because nothing is returned. > > Jeff > > > > 2010/8/10 Jaroslav Záruba <[email protected]> > >> Thanks. :) >> And I assume the allocation does not go the whole way to the very >> Datastore...? I.e. it is faster than let's say delete operation, isn't >> it...? >> >> On Tue, Aug 10, 2010 at 11:54 AM, Jeff Schwartz >> <[email protected]>wrote: >> >>> Batch puts and gets are always faster as they are done in parallel. >>> >>> Jeff >>> >>> 2010/8/9 Jaroslav Záruba <[email protected]> >>> >>>> Thank you, keakon! >>>> >>>> On Tue, Aug 10, 2010 at 4:34 AM, 风笑雪 <[email protected]> wrote: >>>> >>>>> As I know, pre-allocate is nothing about performance, and use single >>>>> put to save entities is faster than put each of them. >>>>> ---------- >>>>> keakon >>>>> >>>>> >>>>> >>>>> 2010/8/10 Jaroslav Záruba <[email protected]>: >>>>> > Hello >>>>> > Could someone tell me which approach is 'cheaper', please? >>>>> > Let's have two entities... >>>>> > - persistedBasket // already persisted entity, holds item IDs >>>>> > - newItem // does not have ID yet >>>>> > Should I put(newItem), pass its ID to persistedBasket and then >>>>> > put(persistedBasket), or is it 'cheaper' to pre-allocate single ID >>>>> for >>>>> > newItem and then do put(persistedBasket, newItem)? >>>>> > In other words, does it make sense to pre-allocate single ID to make >>>>> single >>>>> > put(item1, item2) instead of two consecutive put's? >>>>> > Regards >>>>> > JZ >>>>> > >>>>> > -- >>>>> > 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]<google-appengine%[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]<google-appengine%[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]<google-appengine%[email protected]> >>>> . >>>> For more options, visit this group at >>>> http://groups.google.com/group/google-appengine?hl=en. >>>> >>> >>> >>> >>> -- >>> -- >>> 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]<google-appengine%[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]<google-appengine%[email protected]> >> . >> For more options, visit this group at >> http://groups.google.com/group/google-appengine?hl=en. >> > > > > -- > -- > 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]<google-appengine%[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. 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