Re: TODO items for window functions

On Wed, Dec 31, 2008 at 11:04:41AM -0500, Tom Lane wrote:
> Alvaro Herrera <alvherre@commandprompt.com> writes:
> > Heikki Linnakangas escribi�:
> >> Tom Lane wrote:
> >>> pg_catalog | nth_value | anyelement       | anyelement, integer OVER window
> >> 
> >> That looks like "OVER window" is associated with the "integer", like  
> >> DEFAULT. I don't have any better suggestions, though.
> 
> >   pg_catalog | nth_value | anyelement       | (anyelement, integer) OVER window
> 
> Yeah, I had considered that too, and it has a distinct advantage for
> parameterless functions like rank():
> 
>    Schema   | Name | Result data type | Argument data types 
> ------------+------+------------------+---------------------
>  pg_catalog | rank | bigint           | OVER window
>  pg_catalog | rank | bigint           | () OVER window
> 
> The latter is definitely clearer about what you're supposed to do.

+1 on the latter.

> However, it seems kind of inconsistent to do this for window functions
> unless we also make \df start putting parens around the argument lists
> for regular functions.  Comments?

Would parens around all the argument lists really be so bad?  I'm
thinking not.

Cheers,
David.
-- 
David Fetter <david@fetter.org> http://fetter.org/
Phone: +1 415 235 3778  AIM: dfetter666  Yahoo!: dfetter
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