Re: BUG #4465: GROUP BY is not to SQL standard

You are still missing the point - "functional dependencies" is not a
separate module that can be turned on or off with code, they are inherent in
the database design. According to relational theory any non-key field on a
table is functionally dependent of the key of that table, so if you support
both key and non-key fields on a table then you automatically support
functional dependencies. How can you possibly say otherwise?

Where does it describe in the SQL standards EXACTLY what the term
"functional dependencies" means? Is it the same as in relational theory, or
is it something different?

Tony Marston

http://www.tonymarston.net
http://www.radicore.org

> -----Original Message-----
> From: Greg Stark [mailto:greg(dot)stark(at)enterprisedb(dot)com] On
> Behalf Of Gregory Stark
> Sent: 15 October 2008 02:57
> To: Tony Marston
> Cc: 'Peter Eisentraut'; pgsql-bugs(at)postgresql(dot)org
> Subject: Re: BUG #4465: GROUP BY is not to SQL standard
>
>
> "Tony Marston" <tony(at)marston-home(dot)demon(dot)co(dot)uk> writes:
>
> > I think your definition of "Feature T301 Functional
> Dependencies" is
> > extremely questionable. ... If you support both key and non-key
> > columns on a table then you support functional dependencies whether
> > you like it or not.
>
> An ISO/IEC 9075 conformant implementation must list in its
> documentation which optional features it claims to support.
> Postgres does so at:
>
> http://www.postgresql.org/docs/8.3/static/features.html
>
> In particular note that T301 is listed partway down this list:
>
> http://www.postgresql.org/docs/8.3/static/unsupported-features
-sql-standard.html

> As soon as I point out an SQL standard that you DON'T follow I get a
> barrage of weasel words and pathetic excuses.

Well then.

--
Gregory Stark
EnterpriseDB http://www.enterprisedb.com
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