MySQL: support remaining constraint parts of CREATE/ALTER TABLE

[yoichi]

Brief summary of the change made

Continuing from #3826, I implemented all the parts related to constraints in CREATE TABLE and ALTER TABLE, including CHECK constraint support.

https://dev.mysql.com/doc/refman/8.0/en/create-table.html
https://dev.mysql.com/doc/refman/8.0/en/alter-table.html

Are there any other side effects of this change that we should be aware of?

• It reuses TableConstraintSegment in ALTER TABLE ADD CONSTRAINT, the parse structure of ALTER changes.
• It reuses IndexOptionsSegment in ALTER TABLE, where (SECONDARY_)ENGINE_ATTRIBUTE is not allowed. I think it is not the linter's job to check for all syntax errors, and I did to avoid maintaining each for CREATE TABLE and ALTER TABLE.

Pull Request checklist

• Please confirm you have completed any of the necessary steps below.

• Included test cases to demonstrate any code changes, which may be one or more of the following:

  • .yml rule test cases in test/fixtures/rules/std_rule_cases.
  • .sql/.yml parser test cases in test/fixtures/dialects (note YML files can be auto generated with tox -e generate-fixture-yml).
  • Full autofix test cases in test/fixtures/linter/autofix.
  • Other.

• Added appropriate documentation for the change.

• Created GitHub issues for any relevant followup/future enhancements if appropriate.

[codecov]

Codecov Report

Merging #3827 (202b8b2) into main (69785ed) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##              main     #3827   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files          179       179           
  Lines        13727     13727           
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  Hits         13727     13727           

Impacted Files	Coverage Δ
src/sqlfluff/dialects/dialect_mysql.py	100.00% <ø> (ø)

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[barrywhart]

Why was this deleted? I don't see similar code in TableConstraintSegment.

[barrywhart]

Why was this deleted? I don't see similar code in TableConstraintSegment.

[yoichi]

Why was this deleted? I don't see similar code in TableConstraintSegment.

Deleted pattern was "[UNIQUE] [INDEX | KEY] ... [index_option] ...", and it is replaced by the combination of
"[CONSTRAINT] UNIQUE [INDEX | KEY] ... [index_option] ..." (around line 646) and "{INDEX | KEY} ... [index_option] ..." (around line 703) in TableConstraintSegment.

Deleted pattern also includes a pattern in which both UNIQUE and (INDEX or KEY) are absent, and it is not covered by TableConstraintSegment. I think there is no problem by ignoring it since it is a invalid query.

AnySetOf(...) represents "[index_option]..." and is covered by IndexOptionsSegment.

[barrywhart]

With these changes, is it still possible to use KEY_BLOCK_SIZE? (Strangely, there is no .sql file using this.) Could you please add a test case for it to your PR?

You could use one of the examples from this page: https://dev.mysql.com/doc/refman/5.7/en/innodb-compression-usage.html

[yoichi]

With these changes, is it still possible to use KEY_BLOCK_SIZE? (Strangely, there is no .sql file using this.)

Yes.

Could you please add a test case for it to your PR?

Added in 2512947
Thanks

[barrywhart]

Thanks!