Re: Happy column adding (was RE: [HACKERS] Happy column dropping)

> At 11:55 AM 1/25/00 +0100, Peter Eisentraut wrote:
> >On Tue, 25 Jan 2000, Hiroshi Inoue wrote:
> >
> >> Even default is not allowed in ADD COLUMN now. 
> >> There may be other reasons why they aren't allowed.
> >
> >It's not a matter of *allowed*, it's a parsing deficiency. The fact that
> >there was a default declared gets silently ignored. If y'all allow ;) I
> >would like to fix that (have already started a bit) by perusing the code
> >in parse_func.c:transformCreateStmt and do the same for the alter table
> >add column part. Maybe and add/drop constraint will come out in the end as
> >well.
> 
> However, heap_getattr still won't see the default since it simply
> checks to see of the attribute number falls off the end of the
> tuple and then returns null.
> 
> There's no provision for then pulling out the default value and
> returning it instead.
> 
> I think this is why Tom was implying that add column should really
> alter the table?
> 
> A fully-featured "add column" feature would be very nice, indeed.

Oh, so that is why ALTER TABLE can't have a NOT NULLL default. Makes
total sense.

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