>I have the impression that the indexes get corrupt by a sequence of actions
>
>A couple of things are worth trying
>
>(1) limit the cache
>

>=sys(3050,1, 64 * 1024 * 1024)
>=sys(3050,2, 16 * 1024 * 1024)
>

>
>(2) after every insert/update
>

>flush
>=sys(1104)
>

>
>(3) go top, then seek
>
>
>You'll quickly find out whether the above helps

We're working on buffered data, so I'm not sure 2) will help. I also just found very weird indexes in all stage tables (alltrim(upper(field)) with a filter.

I'm clearing up indexes in stage tables right now, then I resume my tests.