Oh ... and use entity groups. Ikai Lan Developer Programs Engineer, Google App Engine Blog: http://googleappengine.blogspot.com Twitter: http://twitter.com/app_engine Reddit: http://www.reddit.com/r/appengine
On Wed, Jun 15, 2011 at 9:06 PM, Ikai Lan (Google) <[email protected]>wrote: > The most brief explanation I can offer is this: think of the datastore as a > giant key-value store. Design your persistence to this model as much as > possible such that you can do as much using get by key. Minimize the total > phases of RPCs - remember that you can batch get keys. Use queries sparingly > and only when there's no way to do what you want to do using keys. > > Ikai Lan > Developer Programs Engineer, Google App Engine > Blog: http://googleappengine.blogspot.com > Twitter: http://twitter.com/app_engine > Reddit: http://www.reddit.com/r/appengine > > > > On Wed, Jun 15, 2011 at 2:42 PM, Owen <[email protected]> wrote: > >> Ikai >> >> Could you expand on this example a bit, or provide a link that >> discusses it? I'm very interested in best practices for datastore >> structure. I've read a number of comments that indicate that >> ReferenceProperty implementations can be datastore intensive and that >> it's better to find creative ways to denormalize data. This sounds >> like one of them, but I'm having trouble visualizing what you describe >> here. >> >> Thanks, >> Owen >> >> On Jun 14, 10:44 am, "Ikai Lan (Google)" <[email protected]> wrote: >> > Better implementation: define a Person model and a fields Text type >> where >> > you store additional data as a JSON object. Store a "type" attribute. >> Then >> > wrap the Person class with Teacher for all types that have the "Teacher" >> > attribute. >> > >> > Ikai Lan >> > Developer Programs Engineer, Google App Engine >> > Blog:http://googleappengine.blogspot.com >> > Twitter:http://twitter.com/app_engine >> > Reddit:http://www.reddit.com/r/appengine >> > >> > >> > >> > >> > >> > >> > >> > On Tue, Jun 14, 2011 at 3:29 PM, Bruce Aloe <[email protected]> >> wrote: >> > > Hello, >> > >> > > I want to define two kinds (tables): Person (PersonId, age, name) and >> > > Teacher (PersonId, age, name, teaching experience) in my GAE datastore >> > > and Person is the superclass of Teacher. I want to define inheritance >> > > relationship between Person and Teacher, so Teacher kind inherites >> > > PersonId, age, name columns (attributes) from Person kind. >> > >> > > Is there any way to define it in python environment from GAE? >> > >> > > Thanks! >> > >> > > Bruce >> > >> > > -- >> > > 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. >> >> -- >> 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. >> >> > -- 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.
