On Fri, 2021-04-23 at 14:44 +0900, Kyotaro Horiguchi wrote: > > The two examples I know of offhand are in German (eszett "ß" downcases to > > "ss") and Turkish (dotted "Í" downcases to "i", likewise dotless "I" > > According to Wikipedia, "ss" is equivalent to "ß" and their upper case > letters are "SS" and "ẞ" respectively. (I didn't even know of the > existence of "ẞ". AFAIK there's no word begins with eszett, but it > seems that there's a case where "ẞ" appears in a word is spelled only > with capital letters.
This "capital sharp s" is a recent invention that has never got much traction. I notice that on my Fedora 32 system with glibc 2.31 and de_DE.utf8, SELECT lower(E'\u1E9E') = E'\u00DF', upper(E'\u00DF') = E'\u1E9E'; ?column? │ ?column? ══════════╪══════════ t │ f (1 row) which to me as a German speaker makes no sense. But Tom's example was the wrong way around: "ß" is a lower case letter, and the traditional upper case translation is "SS". But the Turkish example is correct: > > downcases to "ı"; one of each of those pairs is an ASCII letter, the > > other is not). Depending on which encoding is in use, these > > Upper dotless "I" and lower dotted "i" are in ASCII (or English > alphabet?). That's interesting. Yes. In languages other than Turkish, "i" is the lower case version of "I", and both are ASCII. Only Turkish has an "ı" (U+0131) and an "İ" (U+0130). That causes annoyance for Turks who create a table named KADIN and find that PostgreSQL turns it into "kadin". Yours, Laurenz Albe
