Re: t_self as system column

On Mon, Jul 5, 2010 at 2:08 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Alvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org> writes:
>> Is there a reason we don't have t_self as one of the system columns that
>> you can examine from SQL?  I'd propose its addition otherwise.
>
> pg_attribute bloat?  I'm a bit hesitant to add a row per table for
> something we've gotten along without for so long, especially something
> with as bizarre a definition as "t_self" has got.
>
> At one time I was hoping to get rid of explicit entries in pg_attribute
> for system columns, which would negate this concern.  I think we're
> stuck with them now, though, because of per-column permissions.

Because someone might want to grant per-column permissions on those
columns? That seems like an awfully thin reason to keep all that
bloat around. I bet the number of people who have granted per-column
permissions on, say, cmax can be counted on one hand - possibly with
five fingers left over.

--
Robert Haas
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