Re: postgres_fdw: using TABLESAMPLE to collect remote sample

On 12/31/22 18:23, Tom Lane wrote:
> Tomas Vondra <tomas(dot)vondra(at)enterprisedb(dot)com> writes:
>> On 12/31/22 05:42, Tom Lane wrote:
>>> ERROR: TABLESAMPLE clause can only be applied to tables and materialized views
>>> I think the patch avoids that, but only accidentally, because
>>> reltuples will be 0 or -1 for a view. Maybe it'd be a good
>>> idea to pull back relkind along with reltuples, and check
>>> that too?
>
>> Not sure. I guess we can rely on reltuples being 0 or -1 in such cases,
>> but maybe it'd be good to at least mention that in a comment? We're not
>> going to use other reltuples values for views etc.
>
> Would anyone ever point a foreign table at a sequence? I guess it
> would be a weird use-case, but it's possible, or was till now.
>

Yeah, it's a weird use case. I can't quite imagine why would anyone do
that, but I guess the mere possibility is sufficient reason to add the
relkind check ...

regards

--
Tomas Vondra
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