Re: Multi-byte character case-folding

On 2020-Jul-06, Tom Lane wrote:

> More generally, I'd be mighty hesitant to change this behavior after
> it's stood for so many years.  I suspect more people would complain
> that we broke their application than would be happy about it.
> 
> Having said that, we are already relying on towlower() in places,
> and could do similarly here if we didn't care about the above issues.

I think the fact that identifiers fail to follow language-specific case
folding rules is more a known gotcha than a desired property, but on
principle I tend to agree that Turkish people would not be happy about
the prospect of us changing the downcasing rule in a major release -- it
would mean having to edit any affected application code as part of a
pg_upgrade process, which is not great.

Now you could say that this can be fixed by adding a GUC that preserves
the old behavior, but generally we don't like that too much.

The counter argument is that there are more future users than there are
current users.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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