Re: [PATCH] backend: compare word-at-a-time in bcTruelen - Mailing list pgsql-hackers

From Simon Riggs
Subject Re: [PATCH] backend: compare word-at-a-time in bcTruelen
Date
Msg-id 1245336292.3895.221.camel@ebony.2ndQuadrant
Whole thread Raw
In response to Re: [PATCH] backend: compare word-at-a-time in bcTruelen  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: [PATCH] backend: compare word-at-a-time in bcTruelen  (Alvaro Herrera <alvherre@commandprompt.com>)
List pgsql-hackers
On Thu, 2009-06-18 at 09:59 -0400, Tom Lane wrote:
> Simon Riggs <simon@2ndQuadrant.com> writes:
> > Why is bcTruelen being called so many *more* times?
> 
> I think you have misunderstood the context.

err, no, I just misread the original text. Possibly a worse error :-?

> It would be way nicer if we could strip trailing blanks on storage,
> and then figure a way to either reconstitute them on output (problem
> here is the output function doesn't have access to typmod) or
> language-lawyer our way to deciding we don't have to.

Is there a spare bit on the varhdr that can be set by datatypes? It
would be useful to have a bit meaning "there is a typmod stored on this
Datum", that would allow the output function to do some special
processing. 

I notice we lose on tuple access also. CHAR(n) is fixed length, but is
treated as variable length for offsets.

-- Simon Riggs           www.2ndQuadrant.comPostgreSQL Training, Services and Support



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