I remember seeing similar stacktraces with an old BaseX version. Could even have been 9.1.

I would inspect[1] the database and run against latest version

/Andy

[1] .https://docs.basex.org/wiki/Commands#INSPECT

On Thu, 29 Jul 2021 at 20:54, Christian Grün <christian.gruen@gmail.com> wrote:

Maybe you could try to find out how the behavior can be triggered from
scratch; I’ll then be happy to look at it.

On Thu, Jul 29, 2021 at 9:27 PM Jonathan Robie <jonathan.robie@gmail.com> wrote:
>
> The easiest way might be to make someone from BaseX a member of a private GitHub repo that has queries, .bxs files, and datasets.
>
> The behavior seems to vary depending on the indexes that have been defined.
>
> Jonathan
>
> On Thu, Jul 29, 2021 at 2:12 PM Christian Grün <christian.gruen@gmail.com> wrote:
>>
>> How can we reproduce this?
>>
>> On Thu, Jul 29, 2021 at 7:59 PM Jonathan Robie <jonathan.robie@gmail.com> wrote:
>> >
>> > Any ideas what this might mean? What should I do?
>> >
>> > Jonathan