Re: What's the point of allow_system_table_mods?

Hi,

On 2019-05-10 19:51:10 +0100, Andrew Gierth wrote:
> >>>>> "Andres" == Andres Freund <andres@anarazel.de> writes:
> 
>  Andres> Why is it so much more dangerous? I've seen plenty of corrupted
>  Andres> clusters due to people doing DML against the catalogs. I'm OK
>  Andres> with adding separate GUCs for both, if we want to do that, but
>  Andres> I do think we shouldn't allow updating the catalogs wthout
>  Andres> having having the superuser explicitly opt into that.
> 
> Be aware that a nonzero number of extensions (postgis especially) do
> catalog DML in their install or update scripts. While you might well
> think they shouldn't do that, in practice there is usually no viable
> alternative.

Sure, but if it's a SUSET GUC that'd not be a huge problem, would it?
They'd need to locally set it, which, sure. But it'd also be a good way
to signal such things to readers.

Greetings,

Andres Freund