Autonumber or unidue id generation

Hi,
I am using a relation(table) which has a artificial key. I want to use this key as the primary key hence is unique. What datatype is associated with this attribute in MS SQL 2000. How can I generate unique id everytime I add a new record to this table ?
Thanks
-SudhakarHi,

I am using a relation(table) which has a artificial key. I want to use this key as the primary key hence is unique. What datatype is associated with this attribute in MS SQL 2000. How can I generate unique id everytime I add a new record to this table ?

Thanks
-Sudhakar

Make the datatype int and set the Identity constraint on that column.
Joydeep|||Your two best choices are either an Identity column (integer), or a GUID with the default set to NewID().|||I would STRONGLY recommend using the GUID if that option is available to you. IDENTITY values are fine for many purposes, and are easy for legacy code to manage, but GUID values are much simpler in the long run. They are easier to use, easier to generate, easier to manage, and very nearly foolproof, at least in my experience.

-PatP|||Well, I use GUIDs almost exclusively, but I don't know that I would recommend them as strongly as Pat. They do have some drawbacks, and I am not talking about their size or the fact they they are difficult to type (stupid arguments...). One of my pet peeves is that I can't apply aggregate functions such as MAX and MIN to GUIDs, which, believe or not, can be handy thing to do some times, such as when eliminating duplicates. You have to cast the GUID as char(36) first, which throws any indexes out the window.