<details class="onebox-details">
    <summary class="onebox-details-summary">
      <h4>
        <a href="https://github.com/apache/spark/pull/31983" target="_blank" rel="noopener nofollow ugc">[SPARK-34882][SQL] Replace if with filter clause in RewriteDistinctAggregates</a>
      </h4>
    </summary>
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What changes were proposed in this pull request?

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   Replaced the agg(if (('gid = 1)) 'cat1 else null) pattern in RewriteDistinctAggregates with agg('cat1) FILTER (WHERE 'gid = 1)

Why are the changes needed?

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   For aggregate functions, that do not ignore NULL values (First, Last or UDAFs) the current approach can return wrong results.

In the added UT there are no nulls in the input testData. The query returned Row(0, 1, 0, 51, 100) before this PR.

Does this PR introduce any user-facing change?

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Bugfix

How was this patch tested?

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UT

<div class="branches">
  <code>apache:master</code> ← <code>tanelk:SPARK-34882_distinct_agg_filter</code>
</div>

<div class="github-info">
  <div class="date">
    opened <span class="discourse-local-date" data-format="ll" data-date="2021-03-28" data-time="20:11:20" data-timezone="UTC">08:11PM - 28 Mar 21 UTC</span>
  </div>

  <div class="user">
    <a href="https://github.com/tanelk" target="_blank" rel="noopener nofollow ugc">
      <img alt="tanelk" src="https://user-images.githubusercontent.com/35076948/181098579-49145a21-8a55-494a-98f7-0f31a1fdd386.png" class="onebox-avatar-inline" width="20" height="20">
      tanelk
    </a>
  </div>

  <div class="lines" title="7 commits changed 2 files with 49 additions and 27 deletions">
    <a href="https://github.com/apache/spark/pull/31983/files" target="_blank" rel="noopener nofollow ugc">
      <span class="added">+49</span>
      <span class="removed">-27</span>
    </a>
  </div>
</div>

  <details class="onebox-details">
    <summary class="onebox-details-summary">
      <h4>
        <a href="https://github.com/mlflow/mlflow/pull/4227" target="_blank" rel="noopener nofollow ugc">Fix flaky spark session creation</a>
      </h4>
    </summary>
    <p class="onebox-details-body">Signed-off-by: harupy &lt;17039389+harupy@users.noreply.github.com&gt;

What changes are proposed in this pull request?

A tempoarary workaround for #4229

I'm investigating why this issue suddenly started happening.

How is this patch tested?

(Details)

Release Notes

Is this a user-facing change?

• No. You can skip the rest of this section.
• Yes. Give a description of this change to be included in the release notes for MLflow users.

(Details in 1-2 sentences. You can just refer to another PR with a description if this PR is part of a larger change.)

What component(s), interfaces, languages, and integrations does this PR affect?

Components

• area/artifacts: Artifact stores and artifact logging
• area/build: Build and test infrastructure for MLflow
• area/docs: MLflow documentation pages
• area/examples: Example code
• area/model-registry: Model Registry service, APIs, and the fluent client calls for Model Registry
• area/models: MLmodel format, model serialization/deserialization, flavors
• area/projects: MLproject format, project running backends
• area/scoring: Local serving, model deployment tools, spark UDFs
• area/server-infra: MLflow server, JavaScript dev server
• area/tracking: Tracking Service, tracking client APIs, autologging

Interface

• area/uiux: Front-end, user experience, JavaScript, plotting
• area/docker: Docker use across MLflow's components, such as MLflow Projects and MLflow Models
• area/sqlalchemy: Use of SQLAlchemy in the Tracking Service or Model Registry
• area/windows: Windows support

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• language/r: R APIs and clients
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How should the PR be classified in the release notes? Choose one:

• rn/breaking-change - The PR will be mentioned in the "Breaking Changes" section
• rn/none - No description will be included. The PR will be mentioned only by the PR number in the "Small Bugfixes and Documentation Updates" section
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<div class="branches">
  <code>mlflow:master</code> ← <code>harupy:fix-spark-address-issue</code>
</div>

<div class="github-info">
  <div class="date">
    opened <span class="discourse-local-date" data-format="ll" data-date="2021-04-06" data-time="06:34:30" data-timezone="UTC">06:34AM - 06 Apr 21 UTC</span>
  </div>

  <div class="user">
    <a href="https://github.com/harupy" target="_blank" rel="noopener nofollow ugc">
      <img alt="harupy" src="https://user-images.githubusercontent.com/35076948/181098580-94a429bb-42d5-4766-99f0-40ae80bd987f.png" class="onebox-avatar-inline" width="20" height="20">
      harupy
    </a>
  </div>

  <div class="lines" title="7 commits changed 3 files with 32 additions and 10 deletions">
    <a href="https://github.com/mlflow/mlflow/pull/4227/files" target="_blank" rel="noopener nofollow ugc">
      <span class="added">+32</span>
      <span class="removed">-10</span>
    </a>
  </div>
</div>