ziyanTOP opened a new pull request, #4413:
URL: https://github.com/apache/flink-cdc/pull/4413

   ## What is the purpose of the change
   
   Fix chunk splitting and binlog event routing issues when MySQL collation 
differs from Java's natural String ordering.
   
   Java \`String.compareTo()\` is case-sensitive (Unicode code point order), 
while MySQL collations like \`utf8mb4_general_ci\` are case-insensitive. This 
mismatch causes chunk boundaries computed by Java to diverge from actual MySQL 
row ordering, leading to premature unbounded chunks, overlapping splits, or 
lost binlog events.
   
   See [FLINK-39749](https://issues.apache.org/jira/browse/FLINK-39749) for 
details.
   
   ## Brief change log
   
   - Introduce \`ChunkKeyCompareMode\` enum: \`DEFAULT\`, \`CASE_INSENSITIVE\`, 
\`BINARY\`
   - \`DEFAULT\`: preserves existing behavior (\`String.compareTo()\`)
   - \`CASE_INSENSITIVE\`: uses \`String.compareToIgnoreCase()\` for Java-side 
comparisons
   - \`BINARY\`: injects \`BINARY\` keyword in SQL predicates and uses 
byte-level comparison in Java
   - Cover all three API layers: DataStream API, Flink SQL, Pipeline YAML
   - Update documentation (EN + ZH) and add test coverage
   
   ## Verifying this change
   
   This change is already covered by existing tests 
(\`MySqlTableSourceFactoryTest\`) and has been verified in a production 
Pipeline job (MySQL -> Paimon) with \`CHAR(36)\` UUID primary key and 
\`utf8mb4_general_ci\` collation.
   
   ## 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): yes (affects 
chunk key comparison in snapshot/binlog phases)
   - Anything that affects deployment or recovery: no
   - The S3 file system connector: no
   
   ## Documentation
   
   - Does this pull request introduce a new feature? yes
   - If yes, how is the feature documented? docs


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