Re: Rename max_parallel_degree?

Robert Haas wrote:
> On Mon, Apr 25, 2016 at 2:58 PM, Alvaro Herrera
> <alvherre(at)2ndquadrant(dot)com> wrote:

> > What about calling it something even simpler, such as "max_parallelism"?
> > This avoids such cargo cult, and there's no implication that it's
> > per-query.
>
> So what would we call the "parallel_degree" member of the Path data
> structure, and the "parallel_degree" reloption? I don't think
> renaming either of those to "parallelism" is going to be an
> improvement.

I think we should define the UI first, *then* decide what to call the
internal variable names. In most cases we're able to call the variables
the same as the user-visible names, but not always and there's no rule
that it must be so. Having source code variable names determine what
the user visible name is seems to me like putting the cart before the
horse.

I think the word "degree" is largely seen as a bad idea: it would become
a somewhat better idea only if we change how it works so that it matches
what other DBMSs do, but you oppose that. Hence my proposal to get rid
of that word in the UI. (My first thought yesterday was to look for
synonyms for the "degree" word, so I got as far as "amount of
parallelism" when I realized that such accompanying words add no value
and so we might as well not have any word there.)

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