Re: Improving GROUP BY? - Mailing list pgsql-general

From Oliver Siegmar
Subject Re: Improving GROUP BY?
Date
Msg-id 200509301538.20376.oliver@siegmar.net
Whole thread Raw
In response to Re: Improving GROUP BY?  (Peter Eisentraut <peter_e@gmx.net>)
List pgsql-general
On Friday 30 September 2005 15:23, Peter Eisentraut wrote:
> Am Freitag, 30. September 2005 09:03 schrieb Oliver Siegmar:
> > - Would it be possible to add a feature to PostgreSQL to allow grouping
> > by unique identifiers only?
> > - Is this requirement (all fields in GROUP BY) based on the SQL standard?
>
> What you describe is called "functional dependencies" in the SQL standard.
> (The query processor would recognize that the non-primary key columns
> "functionally depend" on the primary key and therefore do not have to be
> grouped separately.)  This is definitely a valid feature but PostgreSQL
> does not implement it yet.

Could you add it to the TODO list? ;-)

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