Hi Jeff, On Tue, Oct 12, 2010 at 4:32 PM, Jeff Schwartz <jefftschwa...@gmail.com>wrote:
> Hi Nick, > > From the docs at > http://code.google.com/appengine/docs/java/datastore/queriesandindexes.html#Big_Entities_and_Exploding_Indexes > : > > "You could call an index that refers to multiple properties with multiple > values an "exploding index," because it can get very large with just a few > values." > > I believe the key words in the above are "multiple properties with multiple > values" however I cannot see anywhere where there is a compound index using > multiple properties that include the list property which according to the > above is what would/could create an exploding index. I should preface this > by saying that I am not a python developer so if there is something in the > yaml file that does create this situation I apologize but would you mind > pointing out what in the yaml file is? > The same (list) property multiple times has the same effect as using multiple different properties. When you include a list in a custom index, all the values of the list must be indexed; when you include multiple lists, or multiple instances of the same list, all unique combinations of values must be indexed. -Nick Johnson > > Thanks in advance. > > > > On Tue, Oct 12, 2010 at 11:22 AM, Nick Johnson (Google) < > nick.john...@google.com> wrote: > >> Hi Jeff, >> >> X is a StringListProperty, and it's indexed on multiple times. The number >> of index entries generated for multiple instances of the same list property >> is n!/(n-m)!, where n is the number of elements in the list, and m is the >> number of repeats in the index. >> >> -Nick Johnson >> >> >> On Tue, Oct 12, 2010 at 4:18 PM, Jeff Schwartz >> <jefftschwa...@gmail.com>wrote: >> >>> Hi Nick. It doesn't appear from the orignal poster's example that even if >>> he had 5000 entries (the max) in his list property that that would cause an >>> exploding index. Can you elaborate. >>> >>> >>> >>> On Tue, Oct 12, 2010 at 10:59 AM, Nick Johnson (Google) < >>> nick.john...@google.com> wrote: >>> >>>> Hi Eric, >>>> >>>> This is a classic 'exploding' index. With 10 elements in the list, this >>>> index will try to generate 10*9*8*7*6 = 30,240 index entries - far above >>>> the >>>> limit. It's not possible to build this index. Consider restructuring your >>>> data, or using merge join queries. >>>> >>>> -Nick Johnson >>>> >>>> >>>> On Tue, Oct 12, 2010 at 3:37 PM, Eric Ka Ka Ng <ngk...@gmail.com>wrote: >>>> >>>>> I would like to build an index for the following entity >>>>> >>>>> Class entityA (db.Model): >>>>> X db.StringListProperty() >>>>> Y db.IntegerProperty() >>>>> Z db.IntegerProperty() >>>>> >>>>> >>>>> >>>>> in index.yaml >>>>> >>>>> - kind: entityA >>>>> >>>>> properties: >>>>> >>>>> - name: Y >>>>> >>>>> - name: X >>>>> >>>>> - name: X >>>>> >>>>> - name: X >>>>> >>>>> - name: X >>>>> >>>>> - name: X >>>>> >>>>> - name: Z >>>>> >>>>> direction: desc >>>>> >>>>> >>>>> >>>>> but the index cannot be built and is always resulted in Error State >>>>> >>>>> >>>>> Thx now we can vaccum the 'error' index now without being stuck in the >>>>> "building" state and have to send emails to G to ask to mark the index as >>>>> 'Error' >>>>> >>>>> >>>>> But I have tried several times to vaccum the index, then re-build, but >>>>> always fail >>>>> >>>>> >>>>> >>>>> May i know why it keeps in failing? The StringList property X usually >>>>> contains 5-10 strings. >>>>> >>>>> >>>>> Best Regards, >>>>> >>>>> Eric >>>>> >>>>> -- >>>>> 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<google-appengine%2bunsubscr...@googlegroups.com> >>>>> . >>>>> For more options, visit this group at >>>>> http://groups.google.com/group/google-appengine?hl=en. >>>>> >>>> >>>> >>>> >>>> -- >>>> Nick Johnson, Developer Programs Engineer, App Engine Google Ireland >>>> Ltd. :: Registered in Dublin, Ireland, Registration Number: 368047 >>>> 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-appeng...@googlegroups.com. >>>> To unsubscribe from this group, send email to >>>> google-appengine+unsubscr...@googlegroups.com<google-appengine%2bunsubscr...@googlegroups.com> >>>> . >>>> 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 google-appeng...@googlegroups.com. >>> To unsubscribe from this group, send email to >>> google-appengine+unsubscr...@googlegroups.com<google-appengine%2bunsubscr...@googlegroups.com> >>> . >>> For more options, visit this group at >>> http://groups.google.com/group/google-appengine?hl=en. >>> >> >> >> >> -- >> Nick Johnson, Developer Programs Engineer, App Engine Google Ireland Ltd. >> :: Registered in Dublin, Ireland, Registration Number: 368047 >> 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-appeng...@googlegroups.com. >> To unsubscribe from this group, send email to >> google-appengine+unsubscr...@googlegroups.com<google-appengine%2bunsubscr...@googlegroups.com> >> . >> 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 google-appeng...@googlegroups.com. > To unsubscribe from this group, send email to > google-appengine+unsubscr...@googlegroups.com<google-appengine%2bunsubscr...@googlegroups.com> > . > For more options, visit this group at > http://groups.google.com/group/google-appengine?hl=en. > -- Nick Johnson, Developer Programs Engineer, App Engine Google Ireland Ltd. :: Registered in Dublin, Ireland, Registration Number: 368047 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. 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