Re: Logical Replication upgrade

On Wed, Apr 15, 2026 at 7:52 AM PG Doc comments form <noreply(at)postgresql(dot)org>
wrote:

> The following documentation comment has been logged on the website:
>
> Page: https://www.postgresql.org/docs/18/logical-replication-upgrade.html
> Description:
>
> Hello there,
>
> I don't know if it's me but I find this sentence quite confusing in its
> current wording:
> All slots on the old cluster must be usable, i.e., there are no slots whose
> pg_replication_slots.conflicting is not true.
>
> The prerequisite is that no replication slot has conflicting=true right?
> So this sentence (the i.e. part) suggests the opposite, as per my
> understanding.
>
> Here is the link (29.13.1):
>
> https://www.postgresql.org/docs/current/logical-replication-upgrade.html#STEPS-TWO-NODE-CIRCULAR-LOGICAL-REPLICATION-CLUSTER:~:text=there%20are%20no%20slots%20whose%20pg_replication_slots.conflicting%20is%20not%20true
>
>
You are correct. Usage of a double-negative should be avoided as a matter
of style, but in this case it actually resolves to an untrue statement.

https://github.com/postgres/postgres/commit/7fdeaf5774d05245e82632e763665ff62db5598e

I've copied the committer for this. Removing the "not" is simple enough;
though writing in the negative sense, while good for an SQL where clause,
does make reading in English more difficult. Would rather say "all slots
must be false" rather than "no slots can be true". The next item regarding
no persistent slots has the same complaint though it is factually correct
as written. Though NULL is a valid value here so maybe the negative
phrasing is indeed necessary...

David J.