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Subject: Re: Can we only add values to enums?
From: "Jonathan S. Katz" <jkatz@postgresql.org>
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 <CAHE3wgiMsjPcrDWpiY37kAv==A+d2JiEWtC0zgBMDs2fmdsZuw@mail.gmail.com>
Date: Fri, 16 Mar 2018 09:14:31 -0400
Cc: brian@traceme.com,
 pgsql-docs@lists.postgresql.org
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 <CAHE3wgiMsjPcrDWpiY37kAv==A+d2JiEWtC0zgBMDs2fmdsZuw@mail.gmail.com>
To: Euler Taveira <euler@timbira.com.br>
Precedence: bulk


> On Mar 15, 2018, at 11:33 PM, Euler Taveira <euler@timbira.com.br> =
wrote:
>=20
> 2018-03-12 20:28 GMT-03:00 PG Doc comments form =
<noreply@postgresql.org>:
>> I need to add a value to an enum, so I found this page, which =
answered my
>> question. However, I found it quite confusing that it only documents =
adding
>> a value. I would expect it to also document how to remove a value =
from an
>> enum? Is this not possible? If not, I consider it a bug. But either =
way, if
>> it is not possible, you should explicitly document it on this page.
>>=20
> If it is not document, this means that it is not supported. It is not
> a bug. It is by design. Read the discussion about this feature at [1].
> Removing a enum value requires a table rewrite. I'm not sure it is
> worth a note.

I would say that=E2=80=99s the exact reason why it should be documented,
so it=E2=80=99s clear that it was by design.

We could also redirect people to DOMAINs if they need more
flexibility in what is added/removed from an =E2=80=9Cenum-like=E2=80=9D =
type.

Jonathan