Re: BUG #18526: 'UPDATE' inconsistency using index scan with 'NOT EXIST' after upgrading to PostgreSQL 16

  I am currently in the process of familiarizing myself with the steps required to compile and run the PostgreSQL code. As this will take some time, I wanted to let you know that I will begin testing the patch as soon as I am ready.  Thank you for your understanding and patience.  

Em sex., 28 de jun. de 2024 às 16:13, Tom Lane <tgl@sss.pgh.pa.us> escreveu:

PG Bug reporting form <noreply@postgresql.org> writes:
> Expected Result: All records that meet the criteria should be updated
> regardless of using index scan or seq scan.
> Actual Result: When PostgreSQL 16 uses index scan, it fails to find and
> update all records. By changing random_page_cost to a value that forces the
> use of seq scan, all records are updated correctly.

I see that the problematic plan involves a Merge Right Anti Join step,
which makes me guess that this is the same bug recently reported in

https://www.postgresql.org/message-id/flat/18522-c7a8956126afdfd0%40postgresql.org

Are you in a position to try the patch posted in that thread?

                        regards, tom lane