The data compression feature in SQL Server 2008 helps compress the data inside a database, and it can help reduce the size of the database. Apart from the space savings, data compression provides another benefit: Because compressed data is stored in fewer pages, queries need to read fewer pages from the disk, thereby improving the performance of I/O intensive workloads. However, extra CPU resources are required on the database server to compress and decompress the data, while data is exchanged with the application. Therefore, it is important to understand the workload characteristics when deciding which tables to compress.  Read more...