Re: superuser unable to modify settings of a system table

On Fri, Jun 4, 2010 at 5:13 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> =A0Is there really a use case for users fiddling with pg_proc, pg_class,
>> etc. directly?
>
> There's a use case for *superusers* to fiddle with them, yes.
> (Superusers are presumed to be adults.) =A0I think I recommend a quick
> UPDATE on some catalog at least once a month on the lists.
>
> You might care to consider the fact that no modern Unix system prevents
> root from doing rm -rf /, even though that's "obviously" disastrous.
> Yet (stretching the analogy all out of shape) there's no convenient user
> tool for rearranging the contents of all the inodes on a filesystem.

Sure.  I guess it boils down to how much use case you think there is
for updating system catalogs directly (rather than using DDL).  I
don't follow all the lists so I haven't seen these recommendations.

>> At any rate, I'd be happy to drop that part of the proposal. =A0It would
>> be a step forward just to permit (even without
>> allow_system_table_mods) those changes which don't alter the structure
>> of the catalog. =A0For ALTER TABLE, the SET STATISTICS, (RE)SET
>> (attribute_option), SET STORAGE, CLUSTER ON, SET WITHOUT CLUSTER, and
>> (RE)SET (reloptions) forms are all things that fall into this
>> category, I believe.
>
> It would be far less work to just drop allow_system_table_mods to SUSET.
> And we wouldn't get questions about which forms of ALTER TABLE require
> it.

I think there's some value in distinguishing between things which are
"only for adults" and things which are "almost certainly a bad idea".

--=20
Robert Haas
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