Thanks, Eric. I am sure he will appreciate everyone's effort here to provide help. I know I sure did when I was starting out. The basics were tough, coming from a pure SQL background as I did (though I did have BDAM, VSAM and hierarchial DB expertise from previous generations - yes, I am an old fart lol and I still have a few COBOL and 360/370 Assembler applications on 80 column punch card decks hidden somewhere. Oh gosh! I am really dating myself here lol), and it if it wasn't for this group's great members and the Google team I'd have gone bonkers quite early in the game.
Jeff On Sat, Dec 4, 2010 at 12:11 PM, Erick Fleming <[email protected]>wrote: > Jeff, I interpreted the meat of his question to be related to advanced > queries. As such I was just pointing him to the two areas of documentation > that spell out how these queries worked (which also has an example of > withLimit). You had already answered his question with a valid response, so > I was just providing the more info. > > On Sat, Dec 4, 2010 at 10:59 AM, Jeff Schwartz <[email protected]>wrote: > >> Odd but I don't see him needing either cursors or 2 indexes to achieve his >> required result and it doesn't even need a filter condition. IMO it just >> requires a descending ordering with a limit of 1. >> >> On Sat, Dec 4, 2010 at 11:38 AM, Erick Fleming <[email protected]>wrote: >> >>> In Java you can use Query cursors to [1] limit your results. As far as >>> aggregate functions (like MIN and MAX) you can use [2] indexes to achieve >>> the similar result (ie. order by age and get the top result) >>> >>> [1] >>> http://code.google.com/appengine/docs/java/datastore/queriesandindexes.html#Query_Cursors >>> <http://code.google.com/appengine/docs/java/datastore/queriesandindexes.html#Query_Cursors> >>> [2] >>> http://code.google.com/appengine/docs/java/datastore/queriesandindexes.html#Introducing_Indexes >>> <http://code.google.com/appengine/docs/java/datastore/queriesandindexes.html#Introducing_Indexes> >>> On Sat, Dec 4, 2010 at 10:31 AM, Jeff Schwartz >>> <[email protected]>wrote: >>> >>>> Conceptually they are tables, but not in the same sense as SQL tables. >>>> They are more like a hash map and if you think of them in those terms you >>>> will be better served. >>>> >>>> Are you coding in Python or Java. If you are coding in Java then here's >>>> an example: >>>> >>>> query(Some.class).order('age').limit(1).get() >>>> >>>> >>>> On Sat, Dec 4, 2010 at 11:16 AM, Zeynel <[email protected]> wrote: >>>> >>>>> On Dec 4, 11:08 am, Tim Hoffman <[email protected]> wrote: >>>>> > Remember there are no tables. Just kinds representing models. >>>>> >>>>> I am confused by this statement. When I look at the Development >>>>> Console - Datastore Viewer; I see a table named after the model. In my >>>>> case, I have a table called User with columns "userEmail", "userName" >>>>> and so on. Each row in this table is what the documentation calls an >>>>> "instance" of the class. So what is the justification for the >>>>> statement that there are no tables? >>>>> >>>>> -- >>>>> 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 Schwartz* >>>> >>>> >>>> -- >>>> 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. >>>> >>> >>> >>> >>> -- >>> Erick Fleming >>> >>> -- >>> 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 Schwartz* >> >> -- >> 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. >> > > > > -- > Erick Fleming > > -- > 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 Schwartz* -- 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.
