Re: 8.3.0 backend segfaults

Alex Hunsaker wrote:
> Precedence: bulk
> Sender: pgsql-bugs-owner(at)postgresql(dot)org
>
> On Wed, Mar 12, 2008 at 9:49 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
>> "Alex Hunsaker" <badalex(at)gmail(dot)com> writes:
>> > On Wed, Mar 12, 2008 at 12:44 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>>
>>
>>>> If you say "none of my stuff is changing any schemas", then I'd guess
>>>>
>> >> that the triggering event is a background autovacuum, which forces
>> >> replan just like an intentional schema change would. Does stopping
>> >> autovacuum make the problem go away?
>>
>> > Yep turning off autovacuum seems to have fixed it. And once I
>> > manually vacuum analyze workers; it blows up almost instantly.
>>
>> Yeah, I was going to suggest that you ought to be able to extract
>> a test case involving doing a manual vacuum in between prepare and
>> execute. I suspect it wouldn't even need to involve more than one
>> session.
>>
>
> Here is what im trying right now with no success:
>
> 3 clients doing this:
> while(1)
> {
> $db->begin_work();
> my $sth = $db->prepare_cached('select * from junk left join
> junk as j on j.junk = junk.junk where junk.junk like ? limit 1;');
> print "VAC!\n";
> sleep 10;
> print "EX!\n";
> $sth->execute('junk') || die "failed: $!";
> $sth->fetchall_arrayref();
> $db->commit();
> $db->{'AutoCommit'} = 0;
> $db->{'AutoCommit'} = 1;
> }
>
> where when it prints VAC I :
> update junk set junk = 'junkab';
> VACUUM ANALYZE verbose junk;
> (also tried deleting, and inserting a bunch of junk...)
>
> 3 other clients doing:
> while(1)
> {
> $db->begin_work();
> my $sth = $db->prepare_cached('select * from junk left join
> junk as j on j.junk = junk.junk where junk.junk like ? limit 1;');
> $sth->execute('junk') || die "failed: $!";
> $sth->fetchall_arrayref();
> $db->rollback();
> }
>
> \d junk
> Table "public.junk"
> Column | Type | Modifiers
> --------+------+-----------
> junk | text |
>
>
Hola, esto (like ? ) generalmente no funciona en un prepared statement,
quizas tu problema este ahi.
proba con un =? , (se que no es lo mismo) y si funciona el problema es
el like

Saludos Fernando