[CALCITE-7405] Pre-process expressions for correlations before building projection in SqlToRelConverter

[ian-bertolacci]

To circumvent the bloat optimizations, it is necessary to provide the correlation variables (if they exist) to the builder.
The main change here is to accomplish the logic done in SqlToRelConverter.getCorrelations without having built the Project node.
In this way we (a) extract the correlation id to use for the RelBuilder, and (b) normalize/resolve the correlation ids and rewrite the expressions; all before invoking the RelBuilder.

I've done my best to reuse existing logic. SqlToRelConverter.getCorrelations and SqlToRelConverter.massageExpressionsForCorrelation require a lot of the same logic for resolving the correlation variables for the current scope, so that was moved to a common utility method (SqlToRelConverter.getCorrelationInfo).

[xuzifu666]

Need to fix CI error first.

[xuzifu666]

Why change .gitignore file?

[ian-bertolacci]

When I run with intellij, git detected a ton of extra files.

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
95.3% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[silundong]

If we create a temporary Project with LogicalProject.create before correlation detection, instead of using RelBuilder.projectNamed, would that resolve the issue? That could be much simpler.

[ian-bertolacci]

@silundong

If we create a temporary Project with LogicalProject.create before correlation detection, instead of using RelBuilder.projectNamed, would that resolve the issue? That could be much simpler.

Thats not an unreasonable suggestion, however I expect that change would also create a lot of test changes, both in this project and anything downstream.
I'll check and see (though it'll take me a few days).

[xiedeyantu]

I prefer a simpler, more intuitive processing logic, even if it affects some of the original plans. As you mentioned, are there other places where similar issues arise, and would it be better to have a unified logic for handling them?