Re: InsertPgAttributeTuple() and attcacheoff

On 14/08/2018 17:52, Robert Haas wrote:
> On Tue, Aug 14, 2018 at 3:50 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> Peter Eisentraut <peter(dot)eisentraut(at)2ndquadrant(dot)com> writes:
>>> It seems to me that it would make sense if InsertPgAttributeTuple() were
>>> to set attcacheoff to -1 instead of taking it from the caller.
>>
>> Looked this over, no objections.
>>
>> I wonder whether we should set that field to -1 when we *read*
>> pg_attribute rows from disk, and be less fussed about what gets written
>> out. The only real advantage is that this'd protect us from foolish
>> manual changes to pg_attribute.attcacheoff entries, but that doesn't
>> seem negligible.
>
> I wouldn't object to forcibly writing in -1 when we read the data, but
> I don't think it's a good idea to let values other than -1 get written
> to the disk. User-visible random nonsense in system catalogs seems
> like too much of a foot-gun to me.

I agree. Committed as presented then.

--
Peter Eisentraut http://www.2ndQuadrant.com/
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