On the client side, you can handle the UI changes using Javascript/Ajax. The problem is modeling the data in the DAL and the database. If there aren't too many distinct attributes across the types of items, you can use a single database table as usual, only populating the fields that are relevant for each given type. Another option might be a separate table for each type, again, if there is a relatively small fixed number of types. However, if there are a large number of types and/or attributes, and if you must be able to easily add more and more types/attributes over time (perhaps allowing users to do so directly), then you'll probably need a different modeling approach, such as the EAV model<http://en.wikipedia.org/wiki/Entity%E2%80%93attribute%E2%80%93value_model>. web2py doesn't have any built-in facilities for defining and managing such a model, so you'd have to manually code the CRUD operations for such a model.
This kind of situation is actually better handled by a document-based datastore, such as MongoDB, which doesn't require a fixed schema for each document. The DAL does have an adapter for MongoDB, but it probably wouldn't be useful here because the DAL still expects a fixed schema. You would probably just have to use a native driver and queries with something like MongoDB. Anthony On Tuesday, April 16, 2013 7:34:40 PM UTC-4, Doug Girard wrote: > > I want to create a form which I can add multiple 'items' of different > 'types' that have different 'attributes' > > For example, lets use two types of food, pizza and steak > > You would start by selecting the type of food. Say pizza > > Upon selecting this type you would get more form fields, specific to the > type chosen. Maybe, > > dough: > cheese: > sauce: > topping: > > Where if you had chosen steak, you would get a different set of > attributes. Maybe, > > cut: > rarity: > > etc.. > > I hope I've made myself clear, I'm just a beginner at python and am a bit > stuck. Thank You! > > -- --- You received this message because you are subscribed to the Google Groups "web2py-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
