Re: Make query ID more portable

On Tue, Oct 12, 2021 at 09:40:47AM -0400, Tom Lane wrote:
> Andrey Lepikhov <a.lepikhov@postgrespro.ru> writes:
> > But core jumbling code is good, fast and much easier in support.
> 
> It won't be fast once you stick a bunch of catalog lookups into it.
> I think this is fine as an extension, but it has no chance of being
> accepted in core, just on performance grounds.
> 
> (I'm also not sure that the query ID calculation code is always/only
> invoked in contexts where it's safe to do catalog accesses.)
> 
> A bigger issue is that query ID stability isn't something we are going
> to promise on a large scale --- for example, what if a new release adds
> some new fields to struct Query?  So I'm not sure that "query IDs should
> survive dump/reload" is a useful goal to consider.  It's certainly not
> something that could be reached by anything even remotely like the
> existing code.

Also, the current code handles renames of schemas and objects, but this
would not.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

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