Re: Change of extension name to new name

On 13 October 2016 at 12:37, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Haribabu Kommi <kommi.haribabu@gmail.com> writes:
>> As we are planning to change an extension name from one name to another
>> name because of additional features that are added into this extension,
>
> The usual approach to that is just to increase the version number.
> Why is it necessary to change the name?
>
>> I just thought of adding the support of (ALTER EXTENSION name RENAME To
>> newname), this can be executed before executing the pg_upgrade to the new
>> extension name that is available in the
>> newer version.
>
> And if the user forgets to do that before upgrading?  Not to mention
> that the extension is mostly broken the moment its SQL name no longer
> corresponds to the on-disk control file name.  This seems like
> a non-solution.
>
> In general, once you've shipped something, changing its name is a huge
> pain both for you and your users.  Just say no.

I've touched on a somewhat related case when I wanted to merge two
extensions into one. I took a look and quickly punted on it as way too
messy, but I'm sure there are legitimate use cases for
splitting/merging extensions. That doesn't mean we want to carry
little-used infrastructure for it or that anyone's going to care
enough to implement anything.

Certainly my need wasn't worth doing it for, and it was a simple one.
Doing things like extracting only some parts of an extension into
another extension while maintaining correct dependencies sounds
nightmarish.

So I'm with you. Just don't rename it.

-- Craig Ringer                   http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training & Services