Support ALTER RENAME COLUMN for Distributed Table Engine

Why it matters

This feature enables users to rename columns in tables that use the DISTRIBUTED engine. Previously, ALTER RENAME COLUMN was not supported on distributed tables, which complicated schema migrations and management in distributed ClickHouse clusters. Now, users can apply column renames seamlessly across distributed tables, improving schema evolution workflows and consistency.

How to use it

Use the standard syntax for renaming columns on a DISTRIBUTED table:

ALTER TABLE <distributed_table_name> RENAME COLUMN <old_column_name> TO <new_column_name>;

This command will propagate the rename operation across all underlying shards and replicas of the distributed table.