Обсуждение: BUG #18245: pg_restore accepts same output file name as input file name

The following bug has been logged on the website:

Bug reference:      18245
Logged by:          Mohammad Al Zouabi
Email address:      mb.alzouabi@gmail.com
PostgreSQL version: 14.10
Operating system:   macOS
Description:

Please let it fail when the user passes the same name for the output as the
input. 

I just lost a very important .tar file because I forgot to replace .tar with
.sql.

Thanks!

> On 13 Dec 2023, at 04:39, PG Bug reporting form <noreply@postgresql.org> wrote:

> Please let it fail when the user passes the same name for the output as the
> input.

I think this sounds like a fair restriction, input and output being the same
seems much more likely to be a copy/paste issue than an interesting usecase.
Something like the attached (untested) sketch should be enough I think.

--
Daniel Gustafsson

Hi,

On Wed, Dec 13, 2023 at 09:44:26AM +0100, Daniel Gustafsson wrote:
> > On 13 Dec 2023, at 04:39, PG Bug reporting form <noreply@postgresql.org> wrote:
>
> > Please let it fail when the user passes the same name for the output as the
> > input.
>
> I think this sounds like a fair restriction, input and output being the same
> seems much more likely to be a copy/paste issue than an interesting usecase.

+1

> Something like the attached (untested) sketch should be enough I think.

I'm wondering if it would be worth adding some canonicalize_path() calls while
at it,  ISTM that such mistakes are likely to happen when invoking pg_restore
manually, so having slightly different wording for the exact same file wouldn't
surprising.

Julien Rouhaud <rjuju123@gmail.com> writes:
> On Wed, Dec 13, 2023 at 09:44:26AM +0100, Daniel Gustafsson wrote:
>> Something like the attached (untested) sketch should be enough I think.

> I'm wondering if it would be worth adding some canonicalize_path() calls while
> at it,  ISTM that such mistakes are likely to happen when invoking pg_restore
> manually, so having slightly different wording for the exact same file wouldn't
> surprising.

I'm a little dubious about the value of this; but if we're going to do
it, comparing post-canonicalize_path strings does seem like the right
way.

            regards, tom lane