And to think I was excited to finally get a good explanation of what people usually mean when they say "perfect hashing" (i.e, given a set of keys, construct a hashing function that will assign each key a unique hash so as to avoid collision, with a hash-range that has typically little overhead over the number of keys).

If someone has good resources on that, I'm still interested. I found it hard to fully internalize the stuff I've found when looking a while back. In particular, I'm confused about the (complexity, time) bounds of such a hash construction process.