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From: Tom Lane <tgl@sss.pgh.pa.us>
To: John Naylor <johncnaylorls@gmail.com>
cc: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>,
        Nathan Bossart <nathandbossart@gmail.com>, adam@labkey.com,
        pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #18711: Attempting a connection with a database name longer
 than 63 characters now fails
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Comments: In-reply-to John Naylor <johncnaylorls@gmail.com>
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John Naylor <johncnaylorls@gmail.com> writes:
> On Thu, Nov 21, 2024 at 2:27=E2=80=AFPM Bertrand Drouvot
> <bertranddrouvot.pg@gmail.com> wrote:
> + * If the original name is too long and we see two consecutive bytes
> + * with their high bits set at the truncation point, we might have
> + * truncated in the middle of a multibyte character. In multibyte
> + * encodings, every byte of a multibyte character has its high bit
> + * set.

> Counterexample: Shift JIS -- I don't think we can short-circuit the full=
 check.

Shift JIS is not an allowed server-side encoding, for precisely
that reason.  This whole proposal is based on the assumption that
the string we need to match in pg_database is valid in some
server-side encoding.

			regards, tom lane