[BEAM-6810] Disable CalcRemoveRule to fix trivial projections

[kanterov]

Trivial programs project precisely their input fields, without dropping
or re-ordering them. It turns out that CalcRemoveRule eliminates them,
even if there is a field aliasing. It results in an unexpected
resulting schema of SQL query.

It isn't clear whether it's an issue in Calcite or Beam rules, as a
workaround we disable CalcRemoveRule.

---

Thank you for your contribution! Follow this checklist to help us incorporate your contribution quickly and easily:

• Choose reviewer(s) and mention them in a comment (R: @username).
• Format the pull request title like [BEAM-XXX] Fixes bug in ApproximateQuantiles, where you replace BEAM-XXX with the appropriate JIRA issue, if applicable. This will automatically link the pull request to the issue.
• If this contribution is large, please file an Apache Individual Contributor License Agreement.

Post-Commit Tests Status (on master branch)

Lang	SDK	Apex	Dataflow	Flink	Gearpump	Samza	Spark
Go		---	---	---	---	---	---
Java
Python		---			---	---	---

See .test-infra/jenkins/README for trigger phrase, status and link of all Jenkins jobs.

[kanterov]

R: @amaliujia

[amaliujia]

LGTM. Thanks for finding this issue.

The issue is not because of BeamSQL as this rule is implemented in Calcite. It might not be a bug. Maybe same other rules needed to help alias not dropped.

We are lacking of a rich sets of queries to verify and protect semantic correctness for the long time. The rich query set should define what an implementation behave if it uses Calcite as its SQL dialect. I have no idea if there is such set exists.

[kanterov]

@amaliujia thanks! Agree, I discovered this issue by an internal test suite.

I was looking into CALCITE-1584, it seems that Drill had similar issues, but I didn't check how they fixed it. Let's follow up and see how we can fix that in the right way.

I was surprised to read:

Calcite doesn't promise to retain field names. 95% of the time it can and does, but 5% of the time it really can't retain field names without seriously compromising the Volcano engine.