Avoid populating _schema if the collection is empty in MongoDB connector

[build2create]

Description

This PR is to fix the [issue][1]. Whenever a empty collection was created an entry was populated in default collection _schema. Further upon populating the collection with documents the fields in _schema remained empty. So a workaround there is a check introduced to avoid populating _schema if collection is empty.

Fixes #20972

Release notes

(x) This is not user-visible or is docs only, and no release notes are required.

[cla-bot]

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[cla-bot]

Thank you for your pull request and welcome to our community. We could not parse the GitHub identity of the following contributors: Mithilesh Wachasunder.
This is most likely caused by a git client misconfiguration; please make sure to:

1. check if your git client is configured with an email to sign commits git config --list | grep email
2. If not, set it up using git config --global user.email [email protected]
3. Make sure that the git commit email is configured in your GitHub account settings, see https://github.com/settings/emails

[cla-bot]

Thank you for your pull request and welcome to our community. We could not parse the GitHub identity of the following contributors: Mithilesh Wachasunder.
This is most likely caused by a git client misconfiguration; please make sure to:

1. check if your git client is configured with an email to sign commits git config --list | grep email
2. If not, set it up using git config --global user.email [email protected]
3. Make sure that the git commit email is configured in your GitHub account settings, see https://github.com/settings/emails

[ebyhr]

@cla-bot check

[cla-bot]

The cla-bot has been summoned, and re-checked this pull request!

[mosabua]

👋 @build2create - are you still interested in progressing this PR? If yes, could you address the comments from @ebyhr and fix any build failures?

[build2create]

are you still interested in progressing this PR? If yes, could you address the comments from @ebyhr and fix any build failures?

Yes sorry its been a while will resume on this. Based on the offline chat with @ebyhr seems like a different behaviour with Mongo Compass and Java Client so the test results are different.

[github-actions]

This pull request has gone a while without any activity. Tagging the Trino developer relations team: @bitsondatadev @colebow @mosabua

[github-actions]

Closing this pull request, as it has been stale for six weeks. Feel free to re-open at any time.

[mosabua]

I think @build2create and @ebyhr are going to continue here .. even if slowly. So I am adding the stale-ignore label.

[ebyhr]

@cla-bot check

[cla-bot]

The cla-bot has been summoned, and re-checked this pull request!

[ebyhr]

Let's add a test in follow-up once we find a way to simulate the scenario with Java client.