Re: Constraints involving a system table

ok - so the trigger is the problem. I am aware that one should not mess
around with system tables.

is there a workaround? Maybe creating a view or a function?

Thanks,
Andreas

Richard Huxton wrote:
> Andreas Neumann wrote:
>> Hello,
>>
>> I would like to create a constraint that involves the system table.
>
> I'm afraid you can't (at present, anyway)
>
>> Why is this not working? What other privileges besides "SELECT" would one
>> need to define a constraint?
>
> Well, you need to be able to add a trigger to the system table (which
> you can't do), otherwise it can't check what to do when you delete
> something from pg_namespace.
>
> I think there are two reasons for this:
> 1. Adding a badly coded trigger to a system table can make your life
> very difficult.
> 2. PG uses a few shortcuts behind the scenes when accessing system tables.
>
>

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