Hans Plum <plum(at)giub(dot)uni-bonn(dot)de> writes:
> Take a look at the code and the reactions of PostgreSQL: When I try to
> convert german umlaute, e.g. ,, with lower(), I get no lower letters.
> With upper() it is the same problem vice verser ...
This is determined by locale, not encoding. I think you are not running
the database in the right locale.
regards, tom lane