thanks so much, Tim. I do feel much better now that you've explained the
reasons behind.

Using another client makes sense - will check that out. I did see a bunch
of methods in Kudu API but was hoping to use Impala all the way.

It would be really cool if this Jira will get traction as this is a very
common technique with Hive and Impala on HDFS to swap tables and partitions
to ensure safe process of moving large amounts of data to production tables
https://jira.apache.org/jira/browse/KUDU-2327
Support atomic swap of tables or partitions




On Fri, Jul 27, 2018 at 7:24 PM Tim Armstrong <[email protected]>
wrote:

> Hi,
>   Sorry you ran into this - we don't deliberately want to break workflows
> but it can be tricky if we accidentally expose implementation details.
> There was a previous CVE that resulted from creative use of this
> functionality
> https://lists.apache.org/thread.html/74a163df0cdefcd738c8d18821e69aa69eed2ba5384c0cc255d15c4b@%3Cannounce.apache.org%3E
> so part of the motivation was to simplify the table states and state
> transitions we need to deal with and make it easier to reason about and
> test thoroughly.
>
> We do have a "kudu" label in JIRA if you want to find Kudu-related Impala
> JIRAs. It would be unusual for one open-source project to have veto power
> over changes in another project or to create duplicate JIRAs in multiple
> apache projects for the same work. We do generally work closely with the
> Kudu project.
>
> I think the main workaround would be to use a different Kudu client to
> directly drop the tables. AFAIK the intent of external Kudu tables was
> generally that they would be dropped externally to Impala - I don't think
> we anticipated the "attach then drop" method for
>
> On Fri, Jul 27, 2018 at 8:27 AM, Boris Tyukin <[email protected]>
> wrote:
>
>> So the change was made by Impala developer but it is only relevant to
>> Kudu, taking away the only way to swap tables.
>>
>> I am curious if this change was agreed with Kudu devs. And if changes
>> like that should be tracked by both Kudu and impala JIRAs since Impala is
>> the only way right now to work with Kudu, besides APIs, that requires
>> coding.
>>
>> Is there someone who chairs this type of decisions that impact Impala /
>> Kudu users?
>>
>> This is important for me to understand before we invest into Kudu.
>>
>>
>>
>>
>> On Fri, Jul 27, 2018 at 8:53 AM Boris Tyukin <[email protected]>
>> wrote:
>>
>>> oh no....why?? just why?? we are about to upgrade to 2.12...
>>>
>>> Todd, can this "improvement" get rolled back? This a breaking change and
>>> does not contribute to making anything better. And now the only good way to
>>> swap Kudu tables is gone.
>>>
>>> I am really frustrated. IMPALA-5654
>>> <https://issues.apache.org/jira/browse/IMPALA-5654> should never been
>>> approved without giving users a good alternative.
>>>
>>> Boris
>>>
>>> On Fri, Jul 27, 2018 at 7:10 AM Cliff Resnick <[email protected]> wrote:
>>>
>>>> We sometimes need to replace dimension tables in Kudu in a live
>>>> database. The technique is described here:
>>>>
>>>>
>>>> https://boristyukin.com/how-to-hot-swap-apache-kudu-tables-with-apache-impala/
>>>>
>>>> After 2.12 and IMPALA-5654
>>>> <https://issues.apache.org/jira/browse/IMPALA-5654> it seems there is
>>>> no longer a way to perform the final step, where the hot swap Kudu target
>>>> table is renamed back to the original. It looks like IMPALA-6375
>>>> <https://issues.apache.org/jira/browse/IMPALA-6375> is going to
>>>> address this, but in the meantime is there another workaround we can use?
>>>>
>>>>
>>>>
>>>>
>>>>
>

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