Re: WIP patch: Improve relation size functions such as pg_relation_size() to avoid producing an error when called against a no longer visible relation

On Thu, Dec 22, 2011 at 3:19 PM, Robert Haas <robertmhaas@gmail.com> wrote:
> On Thu, Dec 22, 2011 at 2:02 PM, Phil Sorber <phil@omniti.com> wrote:
>> On Thu, Dec 22, 2011 at 1:33 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>> Robert Haas <robertmhaas@gmail.com> writes:
>>>> I'm wondering if we oughta just return NULL and be done with it.
>>>
>>> +1.  There are multiple precedents for that sort of response, which we
>>> introduced exactly so that "SELECT some_function(oid) FROM some_catalog"
>>> wouldn't fail just because one of the rows had gotten deleted by the
>>> time the scan got to it.  I don't think it's necessary for the
>>> relation-size functions to be any smarter.  Indeed, I'd assumed that's
>>> all that Phil's patch did, since I'd not looked closer till just now.
>>
>> Here it is without the checking for recently dead. If it can't open
>> the relation it simply returns NULL.
>
> I think we probably ought to make pg_database_size() and
> pg_tablespace_size() behave similarly.
>
> --
> Robert Haas
> EnterpriseDB: http://www.enterprisedb.com
> The Enterprise PostgreSQL Company

Changes added.