MIME-Version: 1.0
From: Fujii Masao <masao.fujii@gmail.com>
Date: Fri, 26 Jun 2026 01:46:41 +0900
Message-ID: 
 <CAHGQGwEgxErc54yVOAVWCsr1O=8pgw4oKRPuEQ9mfhkoYGR_XA@mail.gmail.com>
Subject: Document COPY FROM WHERE restrictions on generated and system columns
To: pgsql-docs@lists.postgresql.org
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Hi,

I found that generated columns and system columns cannot be used in
COPY FROM WHERE expressions, but the COPY docs still mentions
only the restriction on subqueries.

So I've created the attached patch which updates the docs to also list
generated columns and system columns as unsupported in COPY FROM WHERE
expressions.

Since generated columns have been rejected in COPY FROM WHERE since
v13, that docs change should be backpatched to all supported branches.
But the system-column restriction was introduced in v19, so that part
does not need to be backpatched.

Thoughts?

Regards,

-- 
Fujii Masao

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