Oh thanks, thats it. I don't know that function.
Now I agree ;-)
Thanks
Daniel
-----Ursprüngliche Nachricht-----
All CAST is doing is changing the type of the datum; it does not change
its value except perhaps as a side effect. A null string is not the
same as an empty string. I don't at all see why you should expect
anything different, especially when the COALESCE() function is already
provided to do exactly what you want.