Quoting Michael Martin <[log in to unmask]>:

> Me again. Still thinking about cases.
> I got to wondering, is there any reason that case markings have to be
> attached to the noun? Could there be a separate word, before or after
> the noun, that designates case? Or maybe the article inflects for case
> instead of the noun? Are there any real languages that do something
> like this?

The former is done by Tagalog, and I guess arguably by Japanese.

As for the later, German chiefly indicates case by changing the article, but
there's also some case endings on the noun. Quite a few nouns, incl most
feminines, are invariable wrt case.