SPARSE COLUMN and COLUMN SET

Another new feature coming up with SQL Server 2008 is SPARSE column. It provides optimal storage by reducing the storage for nullable columns. But there are also downside to it as making a column as SPARSE would put some overhead when a non-null value is read for the column. The group of columns can be setup by making a COLUMN SET while creating a table. The column set would allow all the sparse columns to be updated like a single XML column.