Hi Vijay, You can try the following database model.
class FoodAndAll(db.Model): name = db.StringProperty() parent = db.SelfReferenceProperty() ... ... In my view, this class does all your needs. The class has two properties 1. Name 2. Reference to Parent Class 3. Other optional things So, for the bottom level entities (those who are sub-category of a category), the "parent" will refer to the category. This will go on. It is not at all necessary for a parent to know his child, but it is necessary that a child knows his parents. This is how things will proceed here. I think this Model is best suited for you. For searching, you can do whatever you feel like. Now you have just one Model, one attribute (name). Use judiciously. There is no SMS API. Cheers, -- Pranav Prakash http://codecontrol.bogspot.com On May 1, 10:08 am, 风笑雪 <kea...@gmail.com> wrote: > Why don't you let the category to be a property of your model? > class Food(db.Model): > category1 = ... > category2 = ... > ... > > Food(category1=fruit, category2=red, ...) > > 2009/5/1 Max Ross <maxr+appeng...@google.com <maxr%2bappeng...@google.com>> > > > Hi Vijay, > > > Your questions are going to take some time to answer. Some are easier than > > others. I'd recommend splitting them up into separate posts. > > > Max > > > On Thu, Apr 30, 2009 at 9:27 PM, vijay <mymail.vi...@gmail.com> wrote: > > >> Ping!! > > >> On Thu, Apr 30, 2009 at 5:03 PM, vijay <mymail.vi...@gmail.com> wrote: > > >>> Hello All,I am working on an application and got stuck in design phase I > >>> hope you guyz can help me out. I have several doubts related to > >>> performance > >>> and modelling. > > >>> 1# > >>> In my application i store some hierarchical data and not sure how to do > >>> it. > > >>> for e.g. say you have data organized as > > >>> food > >>> |____fruit > >>> | |___red---Iron----apples > >>> | | | |____something > >>> | | | > >>> | | |___Viatamins ---- litchies > >>> | | > >>> | |___green----Iron-----apples > >>> | |_____Vitamin E ----- guava > >>> | > >>> |____vegetable-------category1 -----category2----category3 > >>> | |________________ > >>> | | |________ > >>> | |________________________________ > >>> | |____ |____ > >>> |____fried |_______ > >>> |__similarly here > > >>> Is there a clean way to store this kind of data in appengine. I mean what > >>> should be classes , their properties etc. > > >>> In my case the sub categories can upto a depth of 10, with each level > >>> having 100s of categories. > >>> I will be executing queries to lookup by any node, so basically i can do > >>> lookup by fruit or apple or food as a whole. > > >>> 2# > >>> My applcation is going to have a search box where user will be writing > >>> his search items, I would like to suggest them the correct word if they > >>> do a > >>> spelling mistake, so if they type frut i wil suggest them to type fruit. > >>> The way i am thinking of implementing it is to for each word entered do a > >>> comparison with each node element with a relaxation of 2, so if the word > >>> matched except at two points i will go ahead and suggest it. I think as i > >>> need to have sequential traversal of all the nodes, which may take a lot > >>> of > >>> time and resources, I should store it somewhere to do faster lookup like > >>> in > >>> memcache, what are your suggestions. > > >>> 3# > >>> Are there any standard APIs to send sms from application. I asked about > >>> this in other thread but haven't got any reply, I hope I will get some > >>> answers this time. > > >>> I am quiet new to web site designing and any other suggestion or some > >>> pointers to general design principles would be great. > > >>> Regards, > >>> Vijay --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
