SQL Server 2008 – Filtered Indexes

SQL Server 2008 introduces a new feature called Filtered Index. A filtered index is a way of adding a WHERE clause to the index definition to get faster access to a subset of the data. For instance if you have a huge table where you are typically only accessing a small part of the table, you can add a filtered index for that small part and save time by having a smaller (filtered index) to access the data that you are looking for.