Thanks for your response John.
The table does have a primary key, so I think that should be fine. And as
far as I know, the table design was not changed, but perhaps something
happened there. I'm not sure how to relink the tables. I didn't design this
database, so I'm afraid I don't know all the ins and outs of its construction.
If you have any other ideas or suggestions, I'd really appreciate your help.
I've tried restoring backups of the database, but the same problem keeps
happening. This is a heavily used database so I need to get it up and