Re: A modest proposal: make parser/rewriter/planner inputs read-only

On 4/5/25 18:46, Tom Lane wrote:
> I'm not planning to pursue this idea Right Now, but it seems like
> something that could happen for v19 or so.  In the meantime I wanted
> to get the ideas down on electrons.
> 
> Thoughts?
I generally like the idea because, for now, I need to be sure that no 
one touched the parse tree before copying it to do additional 
transformations before the optimisation phase.
But what is the way you are proposing here? Do you mean that one more 
entity will be explicitly introduced: a transformed parse tree?
It would open an opportunity for extensions to build a set of 
alternative transformed trees, pass them through the optimisation phase 
and choose the best plan.

-- 
regards, Andrei Lepikhov