How do you prevent Rails from saving many-to-many updates on a model object?
I have an edit page for a model object which has a table on it represented by a has-many relationship. Each table row consists of a label and a series of checkboxes. I am trying to allow the user to add/remove rows from this table (using AJAX), but then either Cancel or Save the updates along with the rest of the info on the page.
Whenever the AJAX calls update the backing model, the relationships are saved in the database rather than held in memory. Is there a way to prevent this, or enable some sort of transaction across http requests, that can rollback in the case of a cancel?
Or is there a better way to accomplish this?