[FLINK-35466][table] Implement star expansion in function calls in SE…

[affo]

…LECT clause

What is the purpose of the change

This PR adds star expansion in SQL in order to gracefully handle statements like SELECT myUDF(*) from MyTable.

Brief change log

• Add a private visitor to perform star expansion of calls to SqlValidatorImpl that re-uses the pre-existing expandStar method in the validator itself
• Add a step in-between unconditional rewrites and validation to expand star (unconditional rewrites would be too early to have information about scopes and perform the expansion, after validation would be too late as the type of * cannot be derived
• Add tests for both parsing and validating

As of now, I did not update the class Javadoc with the lines of the update as I don't know if this is the best way to achieve the result. Waiting for a review to fix the Javadoc in case.

Verifying this change

This change added tests and can be verified as follows:

• Tests for parsing to make sure foo(*) can be parsed as a valid function call
• Tests in validation to verify that the expansion is performed correctly and only under SELECT
• I have local tests for running a full program and check the final result, but don't know if needed

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): no
• The public API, i.e., is any changed class annotated with @Public(Evolving): no
• The serializers: no
• The runtime per-record code paths (performance sensitive): no
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn, ZooKeeper: no
• The S3 file system connector: no

Documentation

• Does this pull request introduce a new feature? no
• If yes, how is the feature documented? NA

[flinkbot]

CI report:

• 5570803 Azure: FAILURE

Bot commands

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• @flinkbot run azure re-run the last Azure build

[davidradl]

I am not an expert on the table planner - but had some basic questions.

1. I am not seeing how we know it is a select * . Is this related to if (outermostNode instanceof SqlSelect) {
2. Will this effect all select * code , include the working non UDF select *'s? If so is there now redundant code we need to remove that dealt with the * later?

[affo]

Thanks you @davidradl for your review!

1. I am not isolating select * for just the select node. This is about the star expansion in function calls only
2. This would not expand * alone, but only in SqlCall. The implementation of that is quite hardcoded in the SqlValidator and I did not touch that. However, I am able to re-use the same expandStar method.

Does this answer your questions?

[davidradl]

how about a quoted * test. To check that the select does not expand