I just bumped into quite big obstacle - almost finishing survey, found that I am unable to activate it, due to column number too high either for postgres or mysql. I know that there's possibility to join few surveys end urls, but I have quite complicated logical structure, and number of variables needed to pass would be rather huge.
My idea is to add new survey attribute that allow creation of huge questionnaires by storing survey data in few tables (ie. every question group in different table) transparently for user.
How do you think? It wouldn't be hard to implement, and will remove 1000/1600/4096 variable limit (which isn't much for complicated survey).