Re: Evidence of Ownership Issues During Restoration of Extension Member Objects

Thanks for the explanation.

On Tue, Jan 28, 2025 at 12:03 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:

> "David G. Johnston" <david.g.johnston@gmail.com> writes:
> > As an aside, none of the use cases are framed to directly motivate why
> you
> > would take the actions described, so we are still just left seeing
> > unnecessary attempts to make unsupported changes to the system
> permissions
> > setup and responding with “don’t do that”.
>
> The short answer here is that dump/restore is not intended to
> reproduce any manual changes you might've made to the contents
> of an extension --- with the sole exception, since around v9.6,
> that it will try to reproduce permissions changes (NOT ownership
> changes) for objects contained in the extension.  TBH, I think
> that part was a misfeature we shouldn't have accepted, because
> it breaks the abstraction that an extension is a black box whose
> contents are described by on-disk script files.
>
> The use-case driving that definition is that dump/restore
> will install whatever version of the extension is considered
> current on the target system, which might well be different
> from what the source system had (which indeed might not be
> available on the target).  So the more the dump script
> assumes about what is in the extension, the more likely it
> is to fail.
>
> You might want to look into pg_upgrade, which has a different
> charter: it tries to reproduce the extension contents exactly.
>
> Anyway, we are not going to accept the described scenario
> as a bug.  As I already said, manual alteration of the contents
> of an extension is unsupported --- and *in particular* that
> means we will not promise that dump/restore does anything
> useful with such cases.
>
> There are certainly things I don't like about what dump/restore
> does with extension object ownership: it doesn't really attempt
> at all to duplicate the extension's original ownership.  But
> anything we might do to fix that would make it even less likely
> that manual alteration of individual member objects' ownership
> would be preserved.
>
>                         regards, tom lane
>