Re: Choosing default collation/ctype

	Laurenz Albe wrote:

> But if you are using "C.UTF-8", the semantics of upper() can change
> between versions, if Unicode is upgraded. 

Oh I see. Sure, "C" is not affected by that.

> That bears a residual risk
> of OS upgrades breaking indexes on upper(col).

OS upgrades don't count in the case of the builtin provider, but
major Postgres upgrades, yes.

> I'd say that the small benefit of better case conversion isn't worth
> the risk.  I'd chose "C", and use a natural language collation explicitly
> on columns where these things matter.

While I understanding the reasoning, I'm of the opposite opinion.
To me the lack of Unicode support in "C" is too annoying to make
it a blanket recommendation as the default locale.


Best regards,
-- 
Daniel Vérité 
https://postgresql.verite.pro/