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

On 4/15/25 19:34, Tom Lane wrote:
> Andrei Lepikhov <lepihov@gmail.com> writes:
>> But what is the way you are proposing here? Do you mean that one more
>> entity will be explicitly introduced: a transformed parse tree?
> 
> No, I wasn't thinking of adding new concepts, just saying that the
> inputs to certain operations need to be treated as read-only.
> What would you envision a "transformed parse tree" being that's not
> what we have today?
I just want to understand how your idea will work. The query_planner 
does the job for subqueries separately. If a query is transformed in 
some way (let's say, an unnecessary join is deleted), we need to change 
references in the parse tree of another subquery, or it will not find 
the reference at the moment of planning, right?

-- 
regards, Andrei Lepikhov