[DISCUSS] Restart the work of introducing TIME/TIMESTAMP WITH TIME ZONE types to Calcite

[Zhenghua Gao]

Hi,

As Consistent timestamp types in Hadoop SQL engines

[1] described,
there are 3 semantics of TIMESTAMP
types all round. Different database vendors and SQL engines implemented
different behaviors and
even different revisions of the SQL standard define timestamp types
differently(See the following depicts)



In CALCITE-1947 [2], TIME/TIMESTAMP WITH LOCAL TIME ZONE (Instant
semantics) was introduced and
the implementation was similar to PostgreSQL's TIME/TIMESTAMP WITH TIME
ZONE (yes, they are making
the mistake to implement the *Instant* semantics for TIME/TIMESTAMP WITH
TIME ZONE types).

CALCITE-208 [3] and CALCITE-1784 [4] want to introduce TIMESTAMP WITH TIME
ZONE and there is no progress for a long time.

So IMO we should restart the work of introducing TIME/TIMESTAMP WITH TIME
ZONE types to Calcite for
the following reasons:

   - It's a SQL Standard data type
   - Some database vendors(ORACLE/SAP/DB2/MS SQL) and SQL
   engines(presto/snowflake) already support it
   - integrate easily for downstream projects

By introducing there types to Calcite, the following works should be
discussed and done:

   - Add TIME/TIMESTAMP WITH TIME ZONE types to optimizer
   - Confirm the physical storage of there types in Calcite (an extra
   information of time zone should be stored)
   - Extend Calcite SQL parser to support new types
   - Confirm the behaviors of builtin operators: CASTing, extract
   - Others (please remind me if I miss anything)

What do you think?  cc @Danny


[1]
https://docs.google.com/document/d/1gNRww9mZJcHvUDCXklzjFEQGpefsuR_akCDfWsdE35Q/edit#
[2] https://issues.apache.org/jira/browse/CALCITE-1947
[3] https://issues.apache.org/jira/browse/CALCITE-208
[4] https://issues.apache.org/jira/browse/CALCITE-1784

*Best Regards,*
*Zhenghua Gao*

Re: Re: [ANNOUNCE] New Calcite PMC chair: Stamatis Zampetakis

[Alessandro Solimando]

Congratulations, Stamatis!

Il Gio 19 Dic 2019, 07:16 Enrico Olivelli  ha scritto:

> Congratulations Stamatis!
>
> Enrico
>
> Il gio 19 dic 2019, 04:40 Rui Wang  ha scritto:
>
> > Congratulations and Thanks Stamatis!
> >
> >
> >
> > -Rui
> >
> > On Wed, Dec 18, 2019 at 6:52 PM XING JIN 
> wrote:
> >
> > > Congratulations Stamatis!
> > >
> > > -Jin
> > >
> > > Chunwei Lei  于2019年12月19日周四 上午10:33写道：
> > >
> > > > Congratulations Stamatis!
> > > >
> > > >
> > > > Best,
> > > > Chunwei
> > > >
> > > >
> > > > On Thu, Dec 19, 2019 at 9:36 AM Danny Chan 
> > wrote:
> > > >
> > > > > Congratulations Stamatis!
> > > > >
> > > > > Best,
> > > > > Danny Chan
> > > > > 在 2019年12月19日 +0800 AM7:37，dev@calcite.apache.org，写道：
> > > > > >
> > > > > > Congratulations Stamatis!
> > > > >
> > > >
> > >
> >
>

Re: [DISCUSS] Remove Kotlin

[Vladimir Sitnikov]

Kevin>and every response was against the change

This ^^ is false.

Haisheng Yuan: "Unless we change $ to other symbol, I am inclined to keep
using Java"
https://lists.apache.org/thread.html/e3cbf20d22f7a4cc870626c0bc41b99430c2cc37318052d083166653%40%3Cdev.calcite.apache.org%3E

Rui Wang: "Can we only use Kotlin for tests that does not evaluate plans?"
https://lists.apache.org/thread.html/99a1c63d2a61aa9e9741a67186874cb97a01bfc706451ce68912939e%40%3Cdev.calcite.apache.org%3E

Vladimir

Re: Re: [ANNOUNCE] New Calcite PMC chair: Stamatis Zampetakis

[Enrico Olivelli]

Congratulations Stamatis!

Enrico

Il gio 19 dic 2019, 04:40 Rui Wang  ha scritto:

> Congratulations and Thanks Stamatis!
>
>
>
> -Rui
>
> On Wed, Dec 18, 2019 at 6:52 PM XING JIN  wrote:
>
> > Congratulations Stamatis!
> >
> > -Jin
> >
> > Chunwei Lei  于2019年12月19日周四 上午10:33写道：
> >
> > > Congratulations Stamatis!
> > >
> > >
> > > Best,
> > > Chunwei
> > >
> > >
> > > On Thu, Dec 19, 2019 at 9:36 AM Danny Chan 
> wrote:
> > >
> > > > Congratulations Stamatis!
> > > >
> > > > Best,
> > > > Danny Chan
> > > > 在 2019年12月19日 +0800 AM7:37，dev@calcite.apache.org，写道：
> > > > >
> > > > > Congratulations Stamatis!
> > > >
> > >
> >
>

Re: Re: [ANNOUNCE] New Calcite PMC chair: Stamatis Zampetakis

[Rui Wang]

Congratulations and Thanks Stamatis!



-Rui

On Wed, Dec 18, 2019 at 6:52 PM XING JIN  wrote:

> Congratulations Stamatis!
>
> -Jin
>
> Chunwei Lei  于2019年12月19日周四 上午10:33写道：
>
> > Congratulations Stamatis!
> >
> >
> > Best,
> > Chunwei
> >
> >
> > On Thu, Dec 19, 2019 at 9:36 AM Danny Chan  wrote:
> >
> > > Congratulations Stamatis!
> > >
> > > Best,
> > > Danny Chan
> > > 在 2019年12月19日 +0800 AM7:37，dev@calcite.apache.org，写道：
> > > >
> > > > Congratulations Stamatis!
> > >
> >
>

Re: [DISCUSS] Remove Kotlin

[Kevin Risden]

>
> Kevin, what is your opinion on removing Quidem language?
>

Completely unrelated to the topic at hand. This is specifically about
Kotlin.

It is sad you mention "code readability" as "little benefit currently" item.


Please don't put words into my mouth. I have nothing wrong with improving
code readability, but this is subjective. Adding an entirely new language
for some minor code readability improvements is a poor tradeoff. The cost
to maintain the new language easily outweighs the multiline strings.
Switching tests from one language to another and reformatting removes the
history for that file. This makes it much harder to maintain tests over
time.

It is not introducing a brand new language. The very same language is used
> in the build scripts.
>

This is a circular argument. You could say that the build scripts language
is not new since its in a few tests. This doesn't lend any credibility to
keeping Kotlin. It is a new language to Calcite. It was added recently
therefore new.

Those are two different items. The discussion re $ is still open, and
> there's no clear answer yet.
> At the same time, in the very same thread, there were explicit opinions
> that "tests that do not use $ might still benefit from improved
> readability".
> The change in [2] is not related to the $-discussion, so I don't see
> whypeople relate them.


The subject of the email was "[DISCUSS] Tests vs multiline strings" and
every response was against the change. The change made in
https://github.com/apache/calcite/commit/b93ec5a9edb7459696385e6adad67b92b6d406d7
is
explicitly switching from Java to Kotlin for multiline strings. The only
substantial change between the two files is the multiline strings. This
absolutely is related to the email thread where 9 replies were against the
change.

The clear answer was do not do it. It is not still open. It is not wait
longer for more people to chime in. It is not wait a bit and push the
change in anyway. It is not start another thread to try to force a change
it. The clear response was do not do it. The change was still made anyway.

It looks like you express an opinion on "let's rewrite everything in
> Kotlin" rather than "let's pick the proper tools on a case by case basis".


This is completely false. This is putting words into my mouth again. This
is not a quote I said in either case.

I am basing my opinion on the amount of friction this has caused in the
community. Multiple email threads where the support to add Kotlin was never
there to begin with means that it is not a perfect tool. Picking any tool
over the community feedback is short term thinking.

Kevin Risden


On Tue, Dec 17, 2019 at 3:30 AM Vladimir Sitnikov <
sitnikov.vladi...@gmail.com> wrote:

> Kevin>Focusing on the technical side of things, I agree that introducing a
> new
> Kevin>language is of little benefit currently
>
> Kevin, what is your opinion on removing Quidem language?
> Focusing on the technical side, it is a standalone language.
> The language is not Java, it has limited tooling, it has a limited set of
> users, it has 0 or so questions on StackOverflow and so on.
>
> Kevin>I agree that introducing a new
> Kevin>language is of little benefit currently
>
> Keeping tests easy to read, easy to edit, easy to create, easy to debug,
> and easy to maintain is hard.
> Making tests easy to read simplifies code reviews that pay off in the long
> run.
> It is sad you mention "code readability" as "little benefit currently"
> item.
>
> Kevin>surprised that a change went in to
> Kevin>switch to Kotlin especially after the discussion that is happening on
> the
> Kevin>mailing list.
>
> Those are two different items. The discussion re $ is still open, and
> there's no clear answer yet.
> At the same time, in the very same thread, there were explicit opinions
> that "tests that do not use $ might still benefit from improved
> readability".
>
> The change in [2] is not related to the $-discussion, so I don't see why
> people relate them.
>
> Kevin>I agree that introducing a new
> Kevin>language is of little benefit currently
>
> It is not introducing a brand new language. The very same language is used
> in the build scripts.
> The language was designed for interoperability with Java, and it does
> improve things if used appropriately.
>
> For instance, tests like
>
> https://github.com/apache/calcite/pull/1657/commits/0d6bec4140da46af07d58cf07a5e682d61529603#diff-7a7027c499b6e4f5e7448b7b971052f1R85-R94
> are
> much easier to read and update than similar tests in Java.
>
> Note: Kotlin tests are still regular JUnit5 tests, so they get proper
> statistics in the CI outputs like test count, skipped test count, failure
> count, test duration.
>
> Kevin>In my opinion there are more negatives than positives
> Kevin>currently.
>
> What your opinion re Kotlin is based on besides angst and "introducing a
> new language"?
> I can easily relate how the items play for writing tests COBOL, but, well,
> I hope we don't consider 

[jira] [Created] (CALCITE-3610) Fix avatica dockerfiles

[Francis Chuang (Jira)]

Francis Chuang created CALCITE-3610:
---

 Summary: Fix avatica dockerfiles
 Key: CALCITE-3610
 URL: https://issues.apache.org/jira/browse/CALCITE-3610
 Project: Calcite
  Issue Type: Task
  Components: avatica
Reporter: Francis Chuang
Assignee: Francis Chuang


The dockerfiles current reference vatica-standalone-server-1.16.0-shaded.jar. 
These jars no longer exist and are now avatica-standalone-server-1.16.0.jar. 
The dockerifles should be updated to point to these new filenames.



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[DISCUSS] Avatica 1.16.0 dockerfiles broken. Release 1.17.0?

[Francis Chuang]

Upon finalizing the release for Avatica 1.16.0, I noticed that the 
dockerfiles would not build on docker hub. Upon investigation, it 
appears that the file names of the jars on nexus has changed slightly.


The current dockerfiles [1] references 
https://repository.apache.org/content/groups/public/org/apache/calcite/avatica/avatica-standalone-server/${AVATICA_VERSION}/avatica-standalone-server-${AVATICA_VERSION}-shaded.jar


Where as on nexus, they are now called 
avatica-standalone-server-${AVATICA_VERSION}.jar.


- Can anyone confirm if the 
avatica-standalone-server-${AVATICA_VERSION}-shaded.jar and 
avatica-standalone-server-${AVATICA_VERSION}.jar.

jars are suppose to be equivalent?


- Since the docker images for 1.16.0 cannot be built, I think we ought 
to fix the dockerfiles and release a 1.17.0.


Francis

[1] 
https://github.com/apache/calcite-avatica/tree/master/docker/src/main/dockerhub

Re: Re: [ANNOUNCE] New Calcite PMC chair: Stamatis Zampetakis

[XING JIN]

Congratulations Stamatis!

-Jin

Chunwei Lei  于2019年12月19日周四 上午10:33写道：

> Congratulations Stamatis!
>
>
> Best,
> Chunwei
>
>
> On Thu, Dec 19, 2019 at 9:36 AM Danny Chan  wrote:
>
> > Congratulations Stamatis!
> >
> > Best,
> > Danny Chan
> > 在 2019年12月19日 +0800 AM7:37，dev@calcite.apache.org，写道：
> > >
> > > Congratulations Stamatis!
> >
>

Re: Re: [ANNOUNCE] New Calcite PMC chair: Stamatis Zampetakis

[Chunwei Lei]

Congratulations Stamatis!


Best,
Chunwei


On Thu, Dec 19, 2019 at 9:36 AM Danny Chan  wrote:

> Congratulations Stamatis!
>
> Best,
> Danny Chan
> 在 2019年12月19日 +0800 AM7:37，dev@calcite.apache.org，写道：
> >
> > Congratulations Stamatis!
>

Re: Re: [ANNOUNCE] New Calcite PMC chair: Stamatis Zampetakis

[Danny Chan]

Congratulations Stamatis!

Best,
Danny Chan
在 2019年12月19日 +0800 AM7:37，dev@calcite.apache.org，写道：
>
> Congratulations Stamatis!

Re: Feedback for Avatica gradle release

[Francis Chuang]

Another solution is to have the gradle task release the nexus repository 
and poll it until it's completely released. Then once that's done, 
proceed with the rest of the tasks under publishDist.


On 19/12/2019 11:24 am, Francis Chuang wrote:
The Avatica 1.16.0 has been finalized, pending a final announcement. The 
docker hub build was not triggered, so I am in contact with infra to get 
it fixed and the images published.


Overall, the release process using gradle has been very smooth. One 
thing I noticed is that the publishDist task to finalize a release also 
publishes the nexus repository. However, our problem is that we are 
using docker hub to trigger a build to build the docker images when a 
rel/avatica-x.x.x tag is pushed. This causes a problem because 
publishDist will push the tag and then release the neux repository. Even 
then, it can take a few minutes for the nexus repository to be 
published. In the meantime, if the docker hub build was triggered, it 
will fail because the artifacts have not been published to nexus yet.


I think we should disable the publishing of the nexus repository for the 
publishDist task in avatica. We should manually publish it and confirm 
that the release is successful. Once that's done, we execute 
publishDist, which will also push the release tag to git and trigger the 
docker hub builds.


What do you guys think?

Francis

Feedback for Avatica gradle release

[Francis Chuang]

The Avatica 1.16.0 has been finalized, pending a final announcement. The 
docker hub build was not triggered, so I am in contact with infra to get 
it fixed and the images published.


Overall, the release process using gradle has been very smooth. One 
thing I noticed is that the publishDist task to finalize a release also 
publishes the nexus repository. However, our problem is that we are 
using docker hub to trigger a build to build the docker images when a 
rel/avatica-x.x.x tag is pushed. This causes a problem because 
publishDist will push the tag and then release the neux repository. Even 
then, it can take a few minutes for the nexus repository to be 
published. In the meantime, if the docker hub build was triggered, it 
will fail because the artifacts have not been published to nexus yet.


I think we should disable the publishing of the nexus repository for the 
publishDist task in avatica. We should manually publish it and confirm 
that the release is successful. Once that's done, we execute 
publishDist, which will also push the release tag to git and trigger the 
docker hub builds.


What do you guys think?

Francis

Re: Re: [ANNOUNCE] New Calcite PMC chair: Stamatis Zampetakis

[Peter Huang]

Congratulations Stamatis!

On Wed, Dec 18, 2019 at 3:32 PM Haisheng Yuan 
wrote:

> Congratulations Stamatis!
>
> - Haisheng
>
> --
> 发件人：Michael Mior
> 日 期：2019年12月19日 07:23:51
> 收件人：
> 主 题：Re: [ANNOUNCE] New Calcite PMC chair: Stamatis Zampetakis
>
> Congratulations Stamatis!
> --
> Michael Mior
> mm...@apache.org
>
> Le mer. 18 déc. 2019 à 16:43, Kevin Risden  a écrit :
> >
> > Congrats Stamatis!
> >
> > Kevin Risden
> >
> >
> > On Wed, Dec 18, 2019 at 4:12 PM Francis Chuang  >
> > wrote:
> >
> > > Calcite community members,
> > >
> > > I am pleased to announce that we have a new PMC chair and VP as per our
> > > tradition of rotating the chair once a year. I have resigned, and
> > > Stamatis was duly elected by the PMC and approved unanimously by the
> Board.
> > >
> > > Please join me in congratulating Stamatis!
> > >
> > > -Francis
> > >
>

Re: Re: [ANNOUNCE] New Calcite PMC chair: Stamatis Zampetakis

[Haisheng Yuan]

Congratulations Stamatis!

- Haisheng

--
发件人：Michael Mior
日　期：2019年12月19日 07:23:51
收件人：
主　题：Re: [ANNOUNCE] New Calcite PMC chair: Stamatis Zampetakis

Congratulations Stamatis!
--
Michael Mior
mm...@apache.org

Le mer. 18 déc. 2019 à 16:43, Kevin Risden  a écrit :
>
> Congrats Stamatis!
>
> Kevin Risden
>
>
> On Wed, Dec 18, 2019 at 4:12 PM Francis Chuang 
> wrote:
>
> > Calcite community members,
> >
> > I am pleased to announce that we have a new PMC chair and VP as per our
> > tradition of rotating the chair once a year. I have resigned, and
> > Stamatis was duly elected by the PMC and approved unanimously by the Board.
> >
> > Please join me in congratulating Stamatis!
> >
> > -Francis
> >

Re: [ANNOUNCE] New Calcite PMC chair: Stamatis Zampetakis

[Michael Mior]

Congratulations Stamatis!
--
Michael Mior
mm...@apache.org

Le mer. 18 déc. 2019 à 16:43, Kevin Risden  a écrit :
>
> Congrats Stamatis!
>
> Kevin Risden
>
>
> On Wed, Dec 18, 2019 at 4:12 PM Francis Chuang 
> wrote:
>
> > Calcite community members,
> >
> > I am pleased to announce that we have a new PMC chair and VP as per our
> > tradition of rotating the chair once a year. I have resigned, and
> > Stamatis was duly elected by the PMC and approved unanimously by the Board.
> >
> > Please join me in congratulating Stamatis!
> >
> > -Francis
> >

[DISCUSS] Towards Avatica-Go 5.0.0

[Francis Chuang]

Now that Avatica 1.16.0 is just about to be wrapped up, it's time to 
talk about the next release for Avatica-Go, 5.0.0.


Most of the changes are already in place and I will add Avatica-1.16.0 
as a test target.


This release will be a major release because there will be some breaking 
changes to the DSN (connection string) as some parameters were removed. 
These parameters were moved to a struct to allow the setting arbitrary 
connection properties when opening a connection to Avatica.


I plan to have rc0 available for voting within the next couple of days.

Francis

[RESULT] [VOTE] Release apache-calcite-avatica-1.16.0 (release candidate 1)

[Francis Chuang]

Thanks to everyone who has tested the release candidate and given their 
comments and votes.


The tally is as follows.

4 binding +1s:
Danny Chan
Francis Chuang
Kevin Risden
Stamatis Zampetakis

1 non-binding +1s:
Rui Wang

No 0s or -1s.

Therefore, I am delighted to announce that the proposal to release 
Apache Calcite Avatica 1.16.0 has passed.


Thanks everyone. We’ll now roll the release out to the mirrors.

There was some discussion regarding producing zip source archive for 
Windows. As Gradle fails on Windows when using source files with LF line 
endings, we should reach some consensus as to whether we need to produce 
a zip archive targeted towards Windows for the next Avatica and Calcite 
releases.


Francis

Re: [ANNOUNCE] New Calcite PMC chair: Stamatis Zampetakis

[Kevin Risden]

Congrats Stamatis!

Kevin Risden


On Wed, Dec 18, 2019 at 4:12 PM Francis Chuang 
wrote:

> Calcite community members,
>
> I am pleased to announce that we have a new PMC chair and VP as per our
> tradition of rotating the chair once a year. I have resigned, and
> Stamatis was duly elected by the PMC and approved unanimously by the Board.
>
> Please join me in congratulating Stamatis!
>
> -Francis
>

[ANNOUNCE] New Calcite PMC chair: Stamatis Zampetakis

[Francis Chuang]

Calcite community members,

I am pleased to announce that we have a new PMC chair and VP as per our 
tradition of rotating the chair once a year. I have resigned, and 
Stamatis was duly elected by the PMC and approved unanimously by the Board.


Please join me in congratulating Stamatis!

-Francis

Re: [DISCUSS] Remove Kotlin

[Stamatis Zampetakis]

Calcite wouldn't be a great project without Julian's and Vladimir's
contributions. Everybody wants the best for the project and we should work
out to find a solution.

I believe that writing is not great to understand somebody's tone and
intentions and many things can be misunderstood. Maybe for this and other
similar issues we should try to hold live  discussions.

Shall we try to organize an online meeting?

Best,
Stamatis

On Wed, Dec 18, 2019, 2:25 AM Albert  wrote:

> I've used the new version calcite with new version of IntelliJ, everything
> works. I like that.
> I can see valadmir put some efforts in this, I respect that. and all effort
> put in to the codebase should be respected.
> from my side, I don't contribute as much now, but occasionally I would look
> at the new stuff added so as long I can REPL the code I am okay with it.
> as for 'kotlin', like when it was first brought up in the calcite mail
> thread, I am curious about that and would be willing to learn more.
>
>
>
> On Wed, Dec 18, 2019 at 7:45 AM Michael Mior  wrote:
>
> > Le mar. 17 déc. 2019 à 15:26, Vladimir Sitnikov
> >  a écrit :
> > >
> > > Vladimir>Quidem, CalciteAssert
> > > Michael>If you want to propose removing either of these, we could have
> a
> > > Michael>discussion about it, but you're talking about code which is
> > already
> > > Michael>heavily used throughout Calcite.
> > >
> > > The point of "we assume contributors are good at Java, thus we must
> keep
> > > the code to be Java-only" is weak.
> > > New contributors will likely see Quidem and CalciteAssert for the first
> > > time, and Java knowledge does not help there.
> > >
> >
> > I didn't make that point. Those are you words.
> >
> > > It does not imply that languages like Quidem and/or CalciteAssert are a
> > bad
> > > fit for their job, but it is wrong to judge
> > > based solely on "it is not Java".
> > >
> > > Michael>The consensus from the discussion you started seems to be that
> > > Michael>Kotlin should not be added to the tests
> > >
> > > It is not like that.
> >
> > I counted at least 5 different contributors stating they did not think
> > Kotlin should be introduced into test code. You seemed to be the only
> > one in the discussion strongly promoting it. If that's not consensus,
> > I must have misinterpreted the discussion.
> >
> > >
> > > Michael>I agree that for these specific tests, readability is improved
> > >
> > > That is exactly my point. There's an improvement, the downsides are
> > small,
> > > so I just committed it.
> > >
> > > Michael>But many tests require more than this
> > >
> > > That is to be discussed on a test by test basis (or use-case by
> > use-case).
> > > For instance, strings (especially, multi-line ones) with $ is an issue
> > for
> > > Kotlin for now.
> > >
> > > Vladimir
> >
>
>
> --
> ~~~
> no mistakes
> ~~
>

[jira] [Created] (CALCITE-3609) calite for hive struct Ineffective optimization

[hezhang (Jira)]

hezhang created CALCITE-3609:


 Summary: calite for hive struct  Ineffective optimization
 Key: CALCITE-3609
 URL: https://issues.apache.org/jira/browse/CALCITE-3609
 Project: Calcite
  Issue Type: Bug
  Components: core
Affects Versions: 1.16.0, 1.10.0
Reporter: hezhang
 Fix For: 1.16.0


student table：
{code:java}
CREATE TABLE `student`(
  `id` int, 
  `info` struct)
ROW FORMAT SERDE 
  'org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe' 
WITH SERDEPROPERTIES ( 
  'colelction.delim'=':', 
  'field.delim'=',', 
  'serialization.format'=',', 
  'serialization.null.format'='NULL')
{code}



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Re: [DISCUSS] Move CalciteAssert and similar "test framework" classes to its own testlib module

[Vladimir Sitnikov]

Julian>All of those changes were done by Vladimir. Not one of these changes
Julian>adds a single feature, or fixes a single bug, in "Calcite the
Julian>product", the library we deliver to our end-users.

Julian, I see you are frustrated that one of your use-cases is broken.
It is really sad it goes like that, and, please understand that it was not
planned.
It looks like to be the only defect so far which is remarkably good.

It is fine to ignore all my emails (except this one, see below).
I'm really surprised to hear "Not one of these changes adds a single
feature or fixes a single bug".

It is not Gradle's/JUnit's/Vladimir's fault that you do not care to
read/ask/investigate regarding features added and bugs fixed.

I see the following options to proceed:
A) You do your due diligence (e.g. read JIRA comments, read mails, ask
somebody, etc, etc), recognize there are both features added and bugs
fixed, and you apologise
B) You apologise, and stop using "Not one of these changes adds or
fixes"-like justifications
C) You prove that the changes indeed "neither add nor fix things". Note:
"Not one of these changes adds or fixes" are your words, and it is you who
should justify them.

Please let me know your vision on the way to proceed here.

I assume we do not count trivial changes like fixing typos here.
Let us consider just the major stuff like "loading code to IDE",
"configuring IDE", "creating new files/classes", "build times", "CI
output", "code style feedback", "integrated testing between Calcite and
Avatica", "release steps", "reproducible builds", "licensing", and so on.

For instance: "Maven-based build was not working after import to IDEA", and
"Gradle-based build is working right after the import".
"Maven-based build did not configure import order" while the current one
configures import order automatically.
"Maven-based build did not configure copyright headers" while the new one
does configure copyright headers, so newly created files have the proper
headers.
^^ the above suggests "C" is not viable.

Julian>After 3 or 4 days, I am still unable to run the
Julian>test and have Intellij show the difference in a pop-up window

You have asked for help exactly 0 times.
Please remember that dev@ list is exactly for sharing knowledge among the
developers.

Julian>I ran into a problem running SqlPrettyWriterTest a few
Julian>days ago[1] that did not exist a few months ago

SqlPrettyWriterTest and DiffRepository were created by yourself.
You are in a much much better position to understand the logic behind
SqlPrettyWriterTest and DiffRepository than anybody else here.

Julian>After 3 or 4 days, I am still unable to run the
Julian>test and have Intellij show the difference in a pop-up window.

Do you mean you've spent 3-4 days trying to figure out how
SqlPrettyWriterTest and DiffRepository work?
Does that suggest it is worth simplifying that code?

AFAIK, there's a PR#1671 with the fix. Does it work for you?

Julian> I can into another, and another

It has no weight as it is not justified.
Please let us know if you happen to run into a real issue.

Vladimir