Add support for row_alias syntax added in MySQL 8.0.19.

[arthurschreiber]

Description

This pull request adds support for the row_alias syntax added in MySQL 8.0.19 for INSERT INTO statements.

Related Issue(s)

#15509

Checklist

• "Backport to:" labels have been added if this change should be back-ported to release branches
• If this change is to be back-ported to previous releases, a justification is included in the PR description
• Tests were added or are not required
• Did the new or modified tests pass consistently locally and on CI?
• Documentation was added or is not required

Deployment Notes

[vitess-bot]

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[arthurschreiber]

Unit tests are failing due to some whitespace changes I accidentally committed. Will fix that later.

[codecov]

Codecov Report

Attention: Patch coverage is 58.33333% with 5 lines in your changes are missing coverage. Please review.

Project coverage is 68.14%. Comparing base (557a9bd) to head (92ad7bc).
Report is 2 commits behind head on main.

Files	Patch %	Lines
go/vt/sqlparser/ast_format.go	58.33%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #15510      +/-   ##
==========================================
+ Coverage   68.12%   68.14%   +0.01%     
==========================================
  Files        1556     1556              
  Lines      195019   195028       +9     
==========================================
+ Hits       132858   132903      +45     
+ Misses      62161    62125      -36     

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[arthurschreiber]

Looks like this increases the number of shift/reduce conflicts from 3 to 7? 🤔 I'm not quite sure why, if anyone could give me a few pointers on how to fix that, I'd be happy to take a stab at it.

[dbussink]

Looks like this increases the number of shift/reduce conflicts from 3 to 7? 🤔 I'm not quite sure why, if anyone could give me a few pointers on how to fix that, I'd be happy to take a stab at it.

@GuptaManan100 is probably the subject matter expert on this topic.

[arthurschreiber]

Okay, I think I understand where the conflicts are coming from.

The insert_data parsing rule used by insert_statement can either be a list of values, or can be a SELECT from a different table. if it's a SELECT, it can contain select_expression which contains as_ci_opt, which conflicts with the AS used by the row alias syntax.

The good thing here is that the row alias syntax can only be used with VALUES or SET. This seems fixable, but will require some refactoring of the parser.

I also noticed that the way insert_or_replace is used can lead to invalid syntax being accepted by the Vitess parser. For example, REPLACE can not be used together with ON DUPLICATE KEY UPDATE - but the parser allows this.

[GuptaManan100]

I'm looking into it