v.21.2Improvements

In case of unexpected exceptions restart background thread for distributed DDL queries execution

In case of unexpected exceptions automatically restart background thread which is responsible for execution of distributed DDL queries. Fixes #17991. #18285 (徐炘).
Automatically restarts the background thread responsible for executing distributed DDL queries when unexpected exceptions occur.

Why it matters

This feature addresses the issue where the background thread executing distributed DDL queries could stop unexpectedly due to exceptions, causing distributed DDL operations to halt. Automatically restarting the thread ensures continuous and reliable execution of distributed DDL statements, improving system stability and reducing manual intervention.

How to use it

The automatic restart behavior is implemented internally and requires no specific user configuration. Users benefit from enhanced stability of distributed DDL queries without any change to their workflows.