With the release of Microsoft SQL Server 2008 R2, the SQL Server Manageability team addressed these struggles by introducing support for data-tier applications to help streamline the deployment, management, and upgrade of database applications. A data tier application, also referred to as a DAC, is a single unit of deployment that contains all the elements used by an application, such as the database application schema, instance level objects, associated database objects, files and scripts, and even a manifest defining the organization’s deployment requirements.