On Tue, Jul 14, 2009 at 10:06 AM, Pashka R.<pashka.rezni...@gmail.com> wrote: > > Hi, > > I guess if you will use bulk delete it would help: > > delete_me = [] > for item in Model.all(keys_only=True): > delete_me.append(item) > db.delete(delete_me)
This is not a good approach. Iterating over a Query fetches results in batches of 20, which means this will require many more round-trips than would otherwise be necessary. A better approach is: db.delete(Model.all(keys_only=True).fetch(BATCH_SIZE)) -Nick Johnson > > > //wbr Pashka R. <pashka.rezni...@gmail.com> > > > > On Mon, Jul 13, 2009 at 20:45, Tony<fatd...@gmail.com> wrote: >> >> There is no such option, but something that will speed up your deletes >> significantly is to do a keys_only query. The query you are currently >> using fetches all 300 entities into memory (including their >> properties, etc) - but you only need the key to delete the entity. >> Try something like "query = Homedata.all(keys_only=True)" and you >> should be able to delete more entities per batch for less cpu. >> However, it's still going to be a long and cpu-intensive operation for >> 25000+ entities. >> >> On Jul 12, 12:53 pm, jacqueslep <jacquesle...@gmail.com> wrote: >>> Hello, >>> i try to delete all records in a datastore, a simple table with a time >>> serie of int values >>> there are more than 25000 entries >>> >>> when i do : >>> >>> homedata_query = Homedata.all() >>> homedatas = homedata_query.fetch(300) >>> db.delete(homedatas) >>> >>> if the fetch count is greater then 300 i receive a timeout >>> so i have to repeat this a huge number of time >>> >>> it did take me about 20 min to do that >>> and it cost 2.38 CPU hours because the CPU sec used /sec was up to 8 >>> This is not useable, i want to store (and be able to delete) more than >>> 100k entries, >>> deleting 300 by 300 would take more than one hour to complete and cost >>> 8h of cpu >>> >>> what is the trick to instant delete, like the -c option in the App >>> Engine SDK ? >>> >>> btw can someone explain how the cpu sec used /sec are computed >> > >> > > > > -- Nick Johnson, App Engine Developer Programs Engineer Google Ireland Ltd. :: Registered in Dublin, Ireland, Registration Number: 368047 --~--~---------~--~----~------------~-------~--~----~ 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-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 -~----------~----~----~----~------~----~------~--~---
