The Datastore is not relational. It is a schemaless object datastore. ( http://code.google.com/appengine/docs/python/datastore/ ) It is sometimes referred to as a "Key/Value" store. There is a decent write up on the topic here: http://www.readwriteweb.com/enterprise/2009/02/is-the-relational-database-doomed.php
Basically throw everything you know about RDBMS out the window. The way i wrapped my head around it, is instead of thinking about your data as rows in a table, you need to think about it as each record is an individual entity, that has the same structure as other entities of the same model. So tables are loosely equivalent to models and rows are loosely equivalent to entities. It has its pro's and con's, and there are definitely some things that will seem much more difficult to do in the Appengine datastore compared to say MySQL, but once you get the hang of it the benefits are plenty. Also, GQL is the syntax used to access the datastore, not really a direct analogue to SQL. On Sep 28, 3:38 pm, walterbyrd <[email protected]> wrote: > I know that big table is not a traditional relational database. It > uses GQL not SQL, right? > > Does big table have no relational capability, or just limited > relational capability? > > If limited, how limited? -- 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.
