Re: [Review] Re: minor patch submission: CREATE CAST ... AS EXPLICIT

On 2013-06-22 15:10:07 -0400, Robert Haas wrote:
> On Sat, Jun 22, 2013 at 9:16 AM, Cédric Villemain
> <cedric(at)2ndquadrant(dot)com> wrote:
> > patch is in unified format and apply on HEAD.
> > patch contains documentation, however I believe 'AS IMPLICIT' is a PostgreSQL
> > extension with special behavior and 'AS EXPLICIT' respect the standard except
> > that PostgreSQL adds only the expression 'AS EXPLICIT' (it is also the default
> > in the standard).
>
> I object to this patch. This patch a new keyword, EXPLICIT, for
> reasons that are strictly cosmetic. Everything that you can do with
> this patch can also be done without this patch. It is not a good idea
> to slow down parsing of every SQL statement we have just so that
> someone can write CREATE CAST .. AS EXPLICIT. Granted, the parsing
> slowdown for just one keyword is probably not noticeable, but it's
> cumulative with every new keyword we add. Adding them to support new
> features is one thing, but adding them to support purely optional
> syntax is, I think, going too far.

What about simply not using a keyword at that location at all? Something
like the attached hack?

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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