Re: Do we still need parent column in pg_backend_memory_context? - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Do we still need parent column in pg_backend_memory_context?
Date
Msg-id 3280090.1722386115@sss.pgh.pa.us
Whole thread Raw
In response to Re: Do we still need parent column in pg_backend_memory_context?  (David Rowley <dgrowleyml@gmail.com>)
Responses Re: Do we still need parent column in pg_backend_memory_context?
List pgsql-hackers
David Rowley <dgrowleyml@gmail.com> writes:
> On Wed, 31 Jul 2024 at 05:19, Melih Mutlu <m.melihmutlu@gmail.com> wrote:
>> After the patch [1] that adds a path column to pg_backend_memory_context, the parent context can also be found in
thepath array. Since there are currently two ways to retrieve information related to the parent of a context, I wonder
whetherwe still want to keep the parent column. 

> My vote is to remove it.

While it's certainly somewhat redundant now, removing it would break
any application queries that are using the column.  Simply adding
a column in a system view is a much easier sell than replacing or
removing one.

Perhaps you can make an argument that nobody would be depending
on that column, but I fear that's wishful thinking.  Or maybe you
can argue that any query using it is already broken --- but I
think that's only true if someone tries to do the specific sort
of recursive traversal that you illustrated.

            regards, tom lane



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