Possible Duplicate:
Backbone.js partial model update
I have system where I have to download a series of objects from a rails app. When they arrive, I add more information onto them, (mainly converting coordinates to google’s LatLng and other overlays for a map).
The problem is that when I save() the model, ALL the attributes are appended to the request, where I only want some of then to save (I don’t want to save the LatLng objects and other overlays, just the attributes that were downloaded)
Possible duplicate question: Backbone.js partial model update
the gist of it is: there is no default support for partially sending a model to the server (at the moment). But if you really need this, it can be done, by overriding the toJSON methods, which are used by the backbone sync functionality.