Re: BUG #19007: Planner fails to choose partial index with spurious 'not null'

Richard Guo <guofenglinux@gmail.com>

From: Richard Guo <guofenglinux@gmail.com>
To: David Rowley <dgrowleyml@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, bryfox@gmail.com, pgsql-bugs@lists.postgresql.org
Date: 2025-12-10T02:11:53Z
Lists: pgsql-bugs
On Fri, Sep 26, 2025 at 6:20 PM Richard Guo <guofenglinux@gmail.com> wrote:
> Here is an updated version of the patch.  In the commit message, I've
> explained why I think the additional call to eval_const_expressions is
> not a performance concern.  I've also added a test case to validate
> that NullTest quals in index expressions can now be reduced.
>
> One concern I have is that this fix can only be applied to master;
> there's no way to backpatch it to v17 or v18.  This means that the
> issue won't exist in v16 or earlier, nor in v19 and later, but it will
> persist in v17 and v18.  I have no idea what we should do for v17 and
> v18.

I've pushed this fix to master.  Still no idea what to do for v17 and
v18.

- Richard