ClickHouse Changelog
ClickHouse 26.3 LTS tightened data serialization and SQL semantics. String serialization now propagates into nested types like Array and Map, making downgrades unsafe but upgrades transparent. The release also corrected NOT operator precedence to match SQL standard—queries relying on the old non-standard binding will produce different results—and removed the experimental hypothesis skip index type and detectProgrammingLanguage function.
ClickHouse 26.3 LTS tightened data type handling and SQL compliance. String serialization versions now propagate to nested types within Arrays, Maps, and Variants—upgrades are safe but downgrades will break access to 26.3-written data. The release also fixed NOT operator precedence to match SQL standards, removed the hypothesis skip index type, and eliminated the experimental detectProgrammingLanguage function.