Re: [HACKERS] alter table

Vince Vielhaber <vev(at)michvhf(dot)com> writes:
> Can a serial type be added to an existing table using ALTER TABLE? If so
> why doesn't it work on hub? If not, I guess that explains why it doesn't
> work, so I'm open to suggestions on how to add it easily...

I'm not sure about this, but I seem to recall that ALTER TABLE ADD
COLUMN doesn't know anything about adding constraints or defaults.
And, of course, the default clause for a serial column is what *really*
makes it go. Given this lack, the fact that ALTER TABLE is also
unprepared to create the underlying sequence object for a SERIAL column
is the least of your worries ;-)

There was some discussion a few months ago about redesigning the support
for SERIAL columns to make them less of an add-on kluge and more of a
real integrated feature. I'd be inclined to think that that should
happen before we try to teach ALTER TABLE about serial columns ---
otherwise it'll just be another kluge in need of replacement. Does
anyone recall what happened with that discussion thread?

regards, tom lane

On 06-Jul-99 Tom Lane wrote:
> Vince Vielhaber <vev(at)michvhf(dot)com> writes:
>> Can a serial type be added to an existing table using ALTER TABLE? If so
>> why doesn't it work on hub? If not, I guess that explains why it doesn't
>> work, so I'm open to suggestions on how to add it easily...
>
> I'm not sure about this, but I seem to recall that ALTER TABLE ADD
> COLUMN doesn't know anything about adding constraints or defaults.
> And, of course, the default clause for a serial column is what *really*
> makes it go. Given this lack, the fact that ALTER TABLE is also
> unprepared to create the underlying sequence object for a SERIAL column
> is the least of your worries ;-)
>
> There was some discussion a few months ago about redesigning the support
> for SERIAL columns to make them less of an add-on kluge and more of a
> real integrated feature. I'd be inclined to think that that should
> happen before we try to teach ALTER TABLE about serial columns ---
> otherwise it'll just be another kluge in need of replacement. Does
> anyone recall what happened with that discussion thread?
>
> regards, tom lane

Now that you mention it I vaguely recall that thread. I'm also thinking
there may be a problem with serial types on hub. I tried using an insert
with select and although it inserted all 106 records, it didn't have a
clue as to what the serial column was. So I dropped the table, dropped
the sequence and created it again. It gives me this:

ERROR: attribute 'mirrorid' not found

I dropped Marc a note about it since I'm about to run out the door. (Baseball
playoffs are here)

Vince.
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