Re: ALTER enums (was Re: [COMMITTERS] pgsql: doc: first draft of Postgres 10 release notes)

On 09/27/2017 06:05 AM, Alvaro Herrera wrote:
> Bruce Momjian wrote:
>> doc: first draft of Postgres 10 release notes
> I noticed that this item
>
> +<!--
> +Author: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
> +2016-09-05 [15bc038f9] Relax transactional restrictions on ALTER TYPE ... ADD V
> +-->
> +<para>
> +Reduce locking required for adding values to enum types (Andrew Dunstan,
> +Tom Lane)
> +</para>
> +
> +<para>
> +Previously it was impossible to run <command>ALTER TYPE ... ADD
> VALUE</> in a
> +transaction block unless the enum type was created in the same block.
> +Now, only references to uncommitted enum values from other transactions
> +is prohibited.
> +</para>
>
> does not really explain this change very clearly. (The release note item
> was slightly changed later, but not in the substance.) It says it's
> about "locking", but it is certainly not about what we normally call
> "locking" in Postgres.
>
> So, firstly I suggest it doesn't belong in the "Locking" section, but
> rather it should be under "Utility Commands" instead. Second, I think
> it should say "Reduce transactional requirements" rather than "reduce
> locking required".
>
> I think there are further changes needed because of commits 175774d2932d
> and 01c5de88ff2, but that's not what I'm on about here, though
> discussion on that is welcome.
>
> Contrary opinions?
>

It looks like this is moot anyway, I think the consensus is to remove
the feature and try again in release 11.

cheers

andrew

--
Andrew Dunstan https://www.2ndQuadrant.com
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