"Oliveiros C," <oliveiros.cristina@marktest.pt> writes:
> If any one can explain me exactly how the order by clause works on varchars,
> I 'd really appreciate it.
It sorts according to the sort order imposed by your locale setting
(see LC_COLLATE in particular).
A lot of locales have weird and wonderful rules that embody somebody's
notion of "dictionary order". If you don't like it, try switching to
C locale. Or you could learn enough about locale definitions to create
your own.
regards, tom lane