The NEWID() function returns a uniqueidentifier for each row of data that is returned.
Execute the following query in the AdventureWorks database:
select top 5 productid, name from production.productorder by newid()
Here are the results:
productid name----------- --------------------------------------------------917 LL Mountain Frame - Silver, 42722 LL Road Frame - Black, 58372 Thin-Jam Hex Nut 8969 Touring-1000 Blue, 60328 Mountain End Caps(5 row(s) affected)
Execute the query again and you get a completely different set of results:
productid name----------- --------------------------------------------------861 Full-Finger Gloves, S440 Lock Nut 16526 HL Shell451 Lock Nut 11406 External Lock Washer 5(5 row(s) affected)