Re: reducing the footprint of ScanKeyword (was Re: Large writable variables)

On Tue, Jan 8, 2019 at 5:31 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
> John Naylor <john(dot)naylor(at)2ndquadrant(dot)com> writes:
> > In the committed keyword patch, I noticed that in common/keywords.c,
> > the array length is defined with
> > ScanKeywordCategories[SCANKEYWORDS_NUM_KEYWORDS]
> > but other keyword arrays just have ...[]. Is there a reason for the difference?
>
> The length macro was readily available there so I used it. AFAIR
> that wasn't true elsewhere, though I might've missed something.
> It's pretty much just belt-and-suspenders coding anyway, since all
> those arrays are machine generated ...

I tried using the available num_keywords macro in plpgsql and it
worked fine, but it makes the lines really long. Alternatively, as in
the attached, we could remove the single use of the core macro and
maybe add comments to the generated magic numbers.

--
John Naylor https://www.2ndQuadrant.com/
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