Hi Timo!  I'm moving away from SQL to DataStream.

On Thu, Feb 11, 2021 at 9:11 AM Timo Walther <twal...@apache.org> wrote:

> Hi Dan,
>
> the order of all joins depends on the order in the SQL query by default.
>
> You can also check the following example (not interval joins though) and
> swap e.g. b and c:
>
> env.createTemporaryView("a", env.fromValues(1, 2, 3));
> env.createTemporaryView("b", env.fromValues(4, 5, 6));
> env.createTemporaryView("c", env.fromValues(7, 8, 9));
>
> System.out.println(env.sqlQuery("SELECT * FROM c, b, a").explain());
>
> So you can reorder the tables in the query if that improves performance.
> For interval joins, we currently don't provide additional algorithms or
> options.
>
> Regards,
> Timo
>
> On 11.02.21 05:04, Dan Hill wrote:
> > Hi!  I was curious if there are docs on how to optimize Flink joins.  I
> > looked around and on the Flink docs and didn't see much.  I see a little
> > on the Configuration page.
> >
> > E.g. one of my jobs has an interval join.  Does left vs right matter for
> > interval join?
>
>

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