Re: nextval() on serial using old, existing value on insert?

If this is a concern, you could use a trigger to ignore the user-provided value or fetch from the sequence.


> On May 11, 2023, at 11:10 AM, Holger Jakobs <holger@jakobs.com> wrote:
>
> Am 11.05.23 um 14:38 schrieb hubert depesz lubaczewski:
>>> On Wed, May 10, 2023 at 10:06:28PM -0700, Wells Oliver wrote:
>>> As a follow up, I've selected max(common_key) from the table and
>>> setval()'ed on the sequence to that +1 and I think that should make this go
>>> away. Any reason why that's insane?
>> If you're on pg 10 or newer, you can make the id to be "generated always
>> as identity" which will make it impossible to provide id value from
>> user, thus making the problem impossible to happen.
>>
>> Best regards,
>>
>> depesz
>
> Impossible to happen by chance. A malicious user could always use OVERRIDING SYSTEM VALUE clause.
>
> Kind Regards,
>
> Holger
>
> --
> Holger Jakobs, Bergisch Gladbach, Tel. +49-178-9759012
>