Re: Out parameters handling

On Sat, Mar 7, 2009 at 11:32 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> On Sat, Mar 7, 2009 at 9:08 AM, Rod Taylor <rod.taylor@gmail.com> wrote:
>>> It wouldn't be so bad if you could assign internal and external column names.
>
>> This is a good point.  Uglifying the parameter names is sort of OK for
>> input parameters, but is much more annoying for output parameters.
>
> How much of this pain would go away if we changed over to the arguably
> correct (as in Or*cle does it that way) scoping for names, wherein the
> parser first tries to match a name against column names of tables of the
> current SQL statement, and only failing that looks to see if they are
> plpgsql variables?

I think that would definitely be an improvement.  Would that mean that
in a query like the following:

SELECT t.id FROM test t WHERE t.id = 17

...it wouldn't consider replacing "t"?  That all by itself would be an
improvement...

I actually feel like the best thing to do would be to error out if
there's an ambiguous reference.  If you write this:

SELECT id FROM foo, bar WHERE foo.a = bar.a

...it will complain if both foo.id and bar.id are defined.  So if I write:

SELECT id FROM foo

...shouldn't it complain if both foo.id and <parameter namespace>.id
are defined?

...Robert