>>>>Why not
>>>>

>>>>REPLACE Ref WITH lcNewRef ALL FOR Ref=lcRef IN Table
>>>>

>>>
>>>Sorry, forgot to mention that after each record update, it has to be logged into another table.
>>
>>You can do that with a Trigger. That way, no matter how you do the change, it will be logged.
>
>Thanks, I will consider that.
>
>For the time being though, I wouldn't mind knowing the speed difference between my examples.
>

You can run some tests to find out.