I dug a bit deeper, as nobody seems to have a clue either. I printed all keynames that I retrieved from the datastore in the order they were retrieved. I repeated this 3 times, each time calling the exact same code. What turns out to happen is that occasionally, the GqlQuery returns the keys in the wrong order! Suddenly, I get the LAST key in the table and all following keys in DESCENDING order. When the GqlQuery randomly flips back to normal, it then goes in ASCENDING order but from almost at the end of the table.
The peculiar thing is that this seems to happen at a particular position in the table each time. The start of the key reversing seems random, but the last 500 are always the same. I'm wondering if the index is broken and that causes the problem, cause I seriously can't think of any other explanation. Just to say, I have a custom descending index on the key_name for this class, if that makes any difference. Can someone from Google please look into this? Thanks, Ben On Dec 11, 2:04 pm, bsb <[email protected]> wrote: > I doubt that, I did get some explixcit timeouts from the fetch, which > went away when I reduced the limit from 500 to 300. So, I think if it > was a timeout, I'd get an exception thrown, no? > > Best, > ben > > On Dec 10, 2:48 pm, Eli Jones <[email protected]> wrote: > > > > > Maybe one of the fetches times out and it just silently fails.. And > > prints out its current count? > > > On 12/10/09, bsb <[email protected]> wrote: > > > > No ideas? Noone? I just don't understand why not all keys are > > > retrieved every time. It doesn't make any sense... > > > > Thanks in advance, > > > Ben > > > > On Dec 8, 6:47 pm, bsb <[email protected]> wrote: > > >> I am trying to cycle through all elements of a table via the remote > > >> API, using a modification of the code snippet > > >> fromhttp://code.google.com/appengine/articles/remote_api.html: > > > >> #---------------------------------------------------- SNIP > > >> ---------------------------------------------------- > > >> query = db.GqlQuery("SELECT __key__ FROM Model_mobileapp ORDER BY > > >> __key__") > > >> apps = query.fetch(500) > > >> total = 0 > > >> while apps: > > >> total = total + len(apps) > > >> query2 = db.GqlQuery("SELECT __key__ FROM Model_mobileapp WHERE > > >> __key__ > :1 ORDER BY __key__", apps[-1]) > > >> apps = query2.fetch(500) > > > >> print "%d" % total > > >> #---------------------------------------------------- SNAP > > >> ---------------------------------------------------- > > > >> However, I'm getting unpredictable behaviour. Sometimes I get the > > >> correct number (104512), sometimes I get 15999, 30999 and all sorts of > > >> other values. > > > >> Does anyone have any clue what this could be caused by? Is there some > > >> sort of magic caching going on for the fetch() command, that return > > >> some keys which are not in the correct sorting order? Could the > > >> (automatic) ascending key index be broken? Any ideas? > > > >> Thanks, > > >> Ben > > > > -- > > > > 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]. > > > For more options, visit this group at > > >http://groups.google.com/group/google-appengine?hl=en. > > > -- > > Sent from my mobile device -- 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]. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
