Re: add modulo (%) operator to pgbench

Robert Haas wrote:
> On Mon, Aug 4, 2014 at 5:20 AM, Fabien COELHO <coelho(at)cri(dot)ensmp(dot)fr> wrote:
> >> This patch is pretty trivial.
> > Another slightly less trivial but more useful version.
> >
> > The issue is that there are 3 definitions of modulo, two of which are fine
> > (Knuth floored division and Euclidian), and the last one much less useful.
> > Alas, C (%) & SQL (MOD) choose the bad definition:-( I really need any of
> > the other two. The attached patch adds all versions, with "%" and "mod"
> > consistent with their C and SQL unfortunate counterparts, and "fmod" and
> > "emod" the sane ones.
>
> Three different modulo operators seems like a lot for a language that
> doesn't even have a real expression syntax, but I'll yield to whatever
> the consensus is on this one.

I wonder if it would be necessary to offer the division operator
semantics corresponding to whatever additional modulo operator we choose
to offer. That is, if we add emod, do we need "ediv" as well?

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Álvaro Herrera http://www.2ndQuadrant.com/
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