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Re: CockroachDB optimizer


All fair points. Thanks for the insight :)
--
Michael Mior
mmior@xxxxxxxxxxxx


Le ven. 9 nov. 2018 à 14:03, Julian Hyde <jhyde@xxxxxxxxxx> a écrit :

> I’m not very impressed with this work. A DSL for query transformation
> rules has been tried in the past - all the way back to EXODUS[1] - but
> there are so many complexities to deal with that it is better to write your
> rules in a full programming language.
>
> They don’t explicitly talk about relational algebra, which means that they
> are still thinking they can do their transformations on the SQL AST. Which
> - as I discovered around 1999, writing my 3rd SQL parser and 2nd optimizer
> - is not going to work because SQL’s scoping rules make everything too
> brittle.
>
> Julian
>
> [1] http://pages.cs.wisc.edu/~dewitt/includes/queryopt/sigmod87.pdf
>
> > On Nov 9, 2018, at 7:16 AM, Michael Mior <mmior@xxxxxxxxxx> wrote:
> >
> > They're not using Calcite. Their code base is in Go and they wrote their
> > own in Go. If you read the blog post, they describe a DSL they built for
> > expressing optimizer rules which is kind of nice although not terribly
> > different from what we're doing with Calcite.
> >
> > --
> > Michael Mior
> > mmior@xxxxxxxxxx
> >
> >
> > Le ven. 9 nov. 2018 à 08:00, Stamatis Zampetakis <zabetak@xxxxxxxxx> a
> > écrit :
> >
> >> Thanks for sharing this Michael!
> >>
> >> I had a look on their blog post but I didn't notice something really
> novel.
> >> It gives me the impression that they re-implemented a Volcano-style
> >> optimizer like the one of Calcite.
> >>
> >> Out of curiosity, are they using Calcite, or they really built
> everything
> >> from scratch?
> >>
> >> Best,
> >> Stamatis
> >>
> >> Στις Παρ, 9 Νοε 2018 στις 2:55 π.μ., ο/η Michael Mior <mmior@xxxxxxxxxx
> >
> >> έγραψε:
> >>
> >>> The folks from Cockroch Labs just shared an interesting blog post on
> the
> >>> development of their optimizer. Could be some interesting lessons in
> >> their
> >>> code base.
> >>>
> >>> https://www.cockroachlabs.com/blog/building-cost-based-sql-optimizer/
> >>>
> >>>
> >>> --
> >>> Michael Mior
> >>> mmior@xxxxxxxxxx
> >>>
> >>
>
>