Robert Frasca (10/16/2009)
I guess I need to learn to read a little more carefully. My apologies. However, I must take one final whack at this dead horse. The fact that the identifiers have English characters doesn't mean that the app displaying these values isn't displaying them in another language. (I know, why would anyone display identifiers, but the fact is, they often do.)
That's misreading the question. English characters in the db have nothing to do with the application. The idea is not for you to pick apart the question and look for an exception. It's to learn something about the simple case.
I would agree with you that the "efficient" work is misleading. It doesn't really define the criteria. I picked varchar, thinking that above 4-5 char, I just do that. I don't think there's been a reason in most apps to not pick it. There might be, and as Hugo mentioned, your app might require dealing with spaces, and then it would be important.
However with 1TB disk drives, and SQL reading in pages, I don't think the storage space, or performance is a big deal. It seems like it's a case of arguing if the Ferrari or the Lambrogini is a better sports car. They're both quick.