schemadiff: FullTextKeyStrategy, handling multiple 'ADD FULLTEXT key' alter options

[shlomi-noach]

Description

MySQL does not support multiple ADD FULLTEXT KEY clauses in the same ALTER TABLE statement.

schemadiff now supports a FullTextKeyStrategy with the following options:

• FullTextKeyDistinctStatements (default): generate distinct ALTER statements when there's more than one ADD FULLTEXT clause; these statements will be valid to run on MySQL
• FullTextKeyUnifyStatements, generate a single ALTER statement with multiple ADD FULLTEXT clauses. Reasons to use this strategy:
  • We will make this statement valid for Vitess's Online DDL
  • MySQL may remove this limitation in the future.

Tests added.

Related Issue(s)

• schemadiff: tracking issue #10203
• Online DDL: tracking issue #6926

Checklist

• "Backport me!" label has been added if this change should be backported
• Tests were added or are not required
• Documentation was added or is not required

Deployment Notes

[vitess-bot]

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