Re: Intermittent errors when fetching cursor rows on PostgreSQL 16

Il 13/01/25 17:19, Adrian Klaver ha scritto:
> On 1/13/25 00:45, Enrico Schenone wrote:
>> Hello, Adrian.
>> As I said days ago, I have arranged a kind of stress test in
>> production environment.
>> I wrote a program that loads a temporary table, loads 2049 rows into
>> them from a baseline_table and finally declare two nested cursors.
>> The first cursor is on the temp table as parent while the second is
>> on a lookup table as child.
>>
>> The program logic is the transposition of one fragment of several
>> production programs that was failing on cursors, and has to be
>> intended as a POC only.
>>
>
>
>> And Well, I'm quite confused: no error at all has been detected, not
>> only on the test programs but in the whole production system. The
>> error was completely disappeared.
>>
>> Then I have stopped the four tasks of the stress test leaving all
>> other services running for a week, and again no error at all.
>>
>> No setup was changed nor servers was rebooted, nor infrastructure has
>> been upgraded during the test period.
>
> You are absolutely sure about the above?
I can say Yes. All test operations has been logged and verified against
the Postgresql log.
The only component not under my control is the Provider's
Infrastructure, but  the infrastructure admin ensured me that no
operation at all has been made. I beleave him because it is a reliable
tecnician end a well known person.
>
>>
>> As a result, at the moment I'm not understood not only Why & Where
>> the error was occurring, but also Why it is disappeared.
>
> Errors that 'fix' themselves are the most frustrating kind, as you
> know in the back of your mind they will likely pop up again.
True, knocking again to my door ... I still can't beleave.
>
>>
>> Anyone may feel free to give me his opinion.
>> For the moment I'll make no other test unless the error is knocking
>> back to my door.
>
> That is all you can do.
>
>>
>> *Enrico Schenone*
>> Software Architect
>>
>
Thanks a lot for your interest in sharing my strange experience.
Best regards.
Enrico

*Enrico Schenone*
Software Architect