Re: Proposing WITH ITERATIVE

Greetings Jonah!

* Jonah H. Harris (jonah(dot)harris(at)gmail(dot)com) wrote:
> On Tue, Apr 28, 2020 at 6:19 AM Andreas Karlsson <andreas(at)proxel(dot)se> wrote:
>
> > Do you have any examples of queries where it would help? It is pretty
> > hard to say how much value some new syntax adds without seeing how it
> > improves an intended use case.
>
> Thanks for the response. I'm currently working on a few examples per Jeff's
> response along with some benchmark information including improvements in
> response time and memory usage of the current implementation. In the
> meantime, as this functionality has been added to a couple of other
> databases and there's academic research on it, if you're interested, here's
> a few papers with examples:
>
> http://faculty.neu.edu.cn/cc/zhangyf/papers/2018-ICDCS2018-sqloop.pdf
> http://db.in.tum.de/~passing/publications/dm_in_hyper.pdf

Nice!

One of the first question that we need to ask though, imv anyway, is- do
the other databases use the WITH ITERATIVE syntax? How many of them?
Are there other approaches? Has this been brought up to the SQL
committee?

In general, we really prefer to avoid extending SQL beyond the standard,
especially in ways that the standard is likely to be expanded. In
other words, we'd really prefer to avoid the risk that the SQL committee
declares WITH ITERATIVE to mean something else in the future, causing us
to have to have a breaking change to become compliant. Now, if all the
other major DB vendors have WITH ITERATIVE and they all work the same
way, then we can have at least some confidence that the SQL committee
will end up defining it in that way and there won't be any issue.

We do have someone on the committee who watches these lists, hopefully
they'll have a chance to comment on this. Perhaps it's already in
discussion in the committee.

Thanks!

Stephen