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? 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-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. > 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. 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