'Parallel Safety' in CBDB style parallel plan

[avamingli]

Cloudberry Database version

No response

What happened

According to https://www.postgresql.org/docs/14/parallel-safety.html

The planner classifies operations involved in a query as either parallel safe, parallel restricted, or parallel unsafe. A parallel safe operation is one that does not conflict with the use of parallel query. A parallel restricted operation is one that cannot be performed in a parallel worker, but that can be performed in the leader while parallel query is in use.

However, in our CBDB style parallel, there is no leader process at all. The parallel restricted concept should be reconsidered.

What you think should happen instead

No response

How to reproduce

NA

Operating System

NA

Anything else

No response

Are you willing to submit PR?

• [ ] Yes, I am willing to submit a PR!

Code of Conduct

• [X] I agree to follow this project's Code of Conduct.