> Displaying the type will be difficult in many tools

> (probably will just show a binary)

I've not had a chance to install sql2005 yet - do the tools provide any support for working with these types of columns, or can you only access them through code?

> only in situations where the values will be

> manipulated in an application where such structures

> are handled easily

I think that's the key. I've been trying to think of anywhere we might like to use them, and the only one I've come up with in one of our apps so far is international phone numbers. We let the user select an international prefix from a drop down list of countries, and then have seperate entry boxes for area code and number. These are then stored as three seperate fields. From the SQL point of view there's little advantage to this (I suppose it would allow us to easilly update should an international dialling code change), so I might be tempted to use a UDT for such a field. Whether it would be worth any ensuing problems though is another matter. It doesn't appear to offer me any real benefits though - all our updates are done via stored procedures, so I'd presumably still have to pass three parameters into the proc. Hmmm