home-key/foreign-key values

This has probably come up before, but here goes... So the docs seem to 
say that :home-key and :foreign-key in db-info can specify either a 
slot or a list of slots, on p. 9. OTOH, on p. 172, I get the impression 
that these should be single slot names. Looking at the code, it looks 
like these are, in fact, expected to be single slot names. Which page 
is right? What does commonsql do here? (I can't find the relevant docs, 
but that's probably just me -- anyone have a pointer?)?

The list of slots thing looks like it would be useful. On a similar 
note, is it possible to place arbitrary restrictions on the joined 
instances returned by the oodml? It would seem that a richer join 
specification would be useful for the OO interface.

Thanks,

Cyrus