Re: [PATCH v1] psql: Do not complete HEADER MATCH for COPY TO

> On Nov 4, 2026, at 09:24, Koshino Taiki <koshino(at)sraoss(dot)co(dot)jp> wrote:
>
> Hi,
>
> I noticed that psql's tab completion suggests MATCH as a value of the
> HEADER option for both directions of COPY.
>
> For example:
>
> COPY t1 TO STDOUT WITH (HEADER <TAB><TAB>
> false MATCH true
>
> However, the documentation says that HEADER MATCH is valid only for
> COPY FROM. If a user selects the suggested "MATCH" candidate for
> COPY TO, the command fails:
>
> COPY t1 TO STDOUT WITH (HEADER MATCH);
> ERROR: cannot use "match" with HEADER in COPY TO
>
> I think it is misleading for tab completion to suggest syntax that is
> explicitly unsupported by the documentation and rejected by the
> server.
>
> The attached patch checks the COPY direction and offers "MATCH" only
> for COPY FROM. The boolean values remain available in both
> directions, and the change applies to both COPY and \copy completion.
>
> Regards,
>
> Taiki Koshino<koshino(at)sraoss(dot)co(dot)jp>
> SRA OSS K.K.
> TEL: 03-5979-2701 FAX: 03-5979-2702
> URL: https://www.sraoss.co.jp/
>
> <v1-0001-psql-Do-not-complete-HEADER-MATCH-for-COPY-TO.patch>

The fix looks good, however, there is an earlier patch [1] already.

[1] https://postgr.es/m/CAF1DzPXjeGHhpgKzEWmpuoxdZWwErN79yRodOkwRYAt7Bdn2BA@mail.gmail.com

Best regards,
--
Chao Li (Evan)
HighGo Software Co., Ltd.
https://www.highgo.com/