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Add Support for Modifying Key Column Types in ClickHouse

Official CH changelog text
Add ability to modify primary and partition key column type from LowCardinality(Type) to Type and vice versa. Also add an ability to modify primary key column type from EnumX to IntX type. Fixes #5604. #18362 (alesapin).
Added the ability to modify primary and partition key column types between LowCardinality(Type) and Type, as well as modify primary key column types from EnumX to IntX.

Why it matters

This feature addresses limitations in altering key column types by allowing users to convert between LowCardinality wrapped types and their base types, and to change EnumX types to integer types for primary keys. It enhances schema flexibility and simplifies key management in ClickHouse.

How to use it

Use the ALTER TABLE command to modify the column type of primary or partition keys between LowCardinality(Type) and Type, or from EnumX to IntX in the primary key. This enables schema changes without the need to recreate tables.

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