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Re: SQL Client Limitations


Hi Eron,

yes, FLINK-9172 covers how the SQL Client will discover ExternalCatalog similar to how it discovers connectors and formats today. The exact design has to be fleshed out but the SQL Client's environment file will declare catalogs and their properties. The SQL Client's gateway will then perform the communication to external systems.

Regards,
Timo

Am 26.08.18 um 04:54 schrieb Eron Wright:
I'd like to better understand how catalogs will work in SQL Client.   I assume we'll be able to reference catalog classes from the environment file (e.g. FLINK-9172).

Thanks

On Tue, Aug 21, 2018 at 4:56 AM Fabian Hueske <fhueske@xxxxxxxxxx <mailto:fhueske@xxxxxxxxxx>> wrote:

    Hi Dominik,

    The SQL Client supports the same subset of SQL that you get with
    Java /
    Scala embedded queries.
    The documentation [1] covers all supported operations.

    There are some limitations because certain operators require
    special time
    attributes (row time or processing time attributes) which are
    monotonically
    increasing.
    Some operators such as a regular join (in contrast to a
    time-windowed join)
    remove the monotonicity property of time attributes such that
    time-based
    operations cannot be applied anymore.

    Best,
    Fabian

    [1] https://ci.apache.org/projects/flink/flink-docs-
    release-1.6/dev/table/sql.html



    2018-08-21 13:27 GMT+02:00 Till Rohrmann <trohrmann@xxxxxxxxxx
    <mailto:trohrmann@xxxxxxxxxx>>:

    > Hi Dominik,
    >
    > I think such a list would be really helpful. I've pulled Timo
    and Fabian
    > into this conversation because they probably know more.
    >
    > Cheers,
    > Till
    >
    > On Mon, Aug 20, 2018 at 12:43 PM Dominik Wosiński
    <wossyn@xxxxxxxxx <mailto:wossyn@xxxxxxxxx>>
    > wrote:
    >
    >> Hey,
    >>
    >> Do we have any list of current limitations of SQL Client available
    >> somewhere or the only way is to go through JIRA issues?
    >>
    >> For example:
    >> I tried to make Group By Tumble Window and Inner Join in one
    query and it
    >> seems that it is not possible currently and I was wondering
    whether it's
    >> and issue with my query or known limitation.
    >>
    >> Thanks,
    >> Best Regards,
    >> Dominik.
    >>
    >