Re: Add column if not exists (CINE)

Robert Haas wrote:
> On Wed, Apr 28, 2010 at 11:20 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Robert Haas <robertmhaas@gmail.com> writes:
>>> I don't believe you are fairly stating the consensus from previous
>>> discussion and I believe that you are actually in the minority on this
>>> one.  I agree that we probably don't need to support this for object
>>> types for which CREATE OR REPLACE is available or can be made
>>> available, but that isn't feasible for all object types - tables and
>>> columns being the obvious examples.
>> What's obvious about it?  In particular, I should think that ADD OR
>> REPLACE COLUMN would usefully be defined as "ADD if no such column,
>> else ALTER COLUMN as necessary to match this spec".  Dropping the
>> ALTER part of that has no benefit except to lazy implementors; it
>> certainly is not more useful to users if they can't be sure of the
>> column properties after issuing the command.
> 
> Actually, that's a good idea.  But how will you handle tables?

What do you mean?

-- 
  Heikki Linnakangas
  EnterpriseDB   http://www.enterprisedb.com