Re: BUG #19354: JOHAB rejects valid byte sequences

Henson Choi <assam258@gmail.com>

From: Henson Choi <assam258@gmail.com>
To: Heikki Linnakangas <hlinnaka@iki.fi>
Cc: Thomas Munro <thomas.munro@gmail.com>, Robert Haas <robertmhaas@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, Jeroen Vermeulen <jtvjtv@gmail.com>, VASUKI M <vasukianand0119@gmail.com>, pgsql-bugs@lists.postgresql.org
Date: 2026-04-14T10:47:07Z
Lists: pgsql-bugs
Hi all,

I'd like to ask for a brief hold on the removal before the patch
is committed.

JOHAB is formally specified in KS C 5601-1992 Annex 3 (later
renumbered KS X 1001:1992), a Korean national standard published
by the Korean Agency for Technology and Standards (KATS). This
document is written in Korean, and I believe a native Korean
speaker reviewing the original standard directly is the most
reliable way to verify the correct byte ranges and resolve the
ambiguity that has been mentioned in this thread.

I am currently looking into the original standard document and
will follow up with a precise specification and a fix patch
shortly.

One point worth considering before removal: JOHAB may be obsolete
for new systems, but legacy Korean data from the 1990s does exist
in old archives, government records, and university systems. As a
client encoding, JOHAB support in PostgreSQL provides a useful
migration path for loading such data. Removing it closes that door
permanently with no way back.

I am Korean, and I would like to take responsibility for verifying
the standard and submitting a proper fix.

Regards,
Henson

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Fix comments for Korean encodings in encnames.c

  2. Fix the inadvertent libpq ABI breakage discovered by Martin Pitt: the

  3. > Tatsuo Ishii wrote: