Re: BUG #13440: unaccent does not remove all diacritics

Tom Lane <tgl@sss.pgh.pa.us> schrieb am 17.06.2015 00:01:48:
 > Also, while my German is nearly nonexistent, I had the idea that sharp-S
 > to "S" would be considered a case-folding transformation not an accent
 > removal.  Comments from German speakers welcome of course.
The sharp-s 'ß' is historically a ligature of two different kinds of s,
of which the first one looks more like an f and the second one looks
either like a normal 's' or a 'z' (that's why it is called 'szlig' in
html). It is usually considered to be a lower-case only character, event
though an uppercase sharp-s has recently been defined. If you are using
an encoding that doesn't support 'ß', the rule is to substitute it with
'ss'. If you want to capitalize a word containing a 'ß', you substitute
it with 'SS'. For sorting purposes, DIN 5007 says that 'ß' should be
treated as 'ss'.

That's just the German point of view. Thinks can be a little bit
different in other german speaking countries, e.g. in Switzerland, where
you may always substite 'ß' with 'ss' (even if your encoding has an 'ß').

In short: I would think that replacing 'ß' with 's' is wrong, and
certainly not an accent removal.

Best regards,

Curd