Just in case someone else comes across this problem I think we have
found the solution. From one of our devs:

***
I found a description of a bug that sounds like it might be exactly what
we are seeing here:
In the sourceforge.net bug tracking notes for Firebird, A. Peshkoff
describes an unregistered bug that was fixed:
"Possible database corruption when you modify/delete the same record
in pre-trigger for which this trigger was called. This issue also was
known as BUGCHECK(291) before."
The SF bug number is 625899, or you can just check out the URL:
sourceforge.net/tracker/index.php?func=detail&aid=625899&group_id=9028&atid=109028

***

-steve

Steve Wiser wrote:

> Hi,
>
> On an Interbase 5.6 database (running on linux) we have a stored
> procedure that runs from cron that has been dying for the past few
> days. When we look in the /usr/interbase/interbase.log I see the following:
>
> linux8 Fri Mar 10 15:34:10 2006
> Database: /usr/interbase/databases/srw.test.gdb
> internal gds software consistency check (cannot find record back
> version (291))
>
> I have narrowed it down to 1 insert statement in the table that seems to
> cause this to happen. However, it looks like it is not the insert
> statement, but maybe something that the triggers run. I am still
> tracing out what the triggers are doing and trying to replicate their
> logic by hand to find out the exact statement that causes the crash.
> These same triggers do run for many other records, it just seems to be
> when I insert 1 particular record that causes this crash.
>
> Anyways, does anyone know what this error means? We have run IBFirstAid
> on the database, but it didn't find any corruption. I repaired a copy
> of it anyways but that didn't make the problem go away. Also gfix -v
> -full doesn't see any problem with the database. And it will backup and
> restore fine. Anyone have any insight into this?
>
> Thanks,
> Steve
>
>
>
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