Yes Larry, there is an index, and yes I´m issuing a SET INDEX TO before updating. That´s ok I guess?

Also the transaction type = 2 and the batchupdatecount=100, I have no idea if that´s a good number, but setting it too high (>=200) produces an error, something about exceeded number of parameters.
BTW, Bifrost? Very interresting choice for a company name!

Michael,
How does one avoid updating the PK if duplicate values are not allowed?

And without a PK, won´t querying the DB later on be awfully slow?

I guess, it´s pretty clear by now that I´m no SQL Server wizard, but please bear with me!

Regards