Specifications

Introduction to Data-Tier Applications CHAPTER 3 43
Data-tier developers using a data-tier application project template in Visual Studio 2010
rst build a DAC and then deploy the DAC package to an instance of SQL Server 2008 R2.
In contrast, database administrators using the Extract Data-Tier Application Wizard in SQL
Server Management Studio generate a DAC from an existing database. The DAC package is
then deployed to a SQL Server 2008 R2 instance. In both methods, the deployment creates a
DAC denition that is stored in the msdb system database and a user database that stores the
objects identied in the DAC denition. Finally, the applications connect to the database associ-
ated with the DAC. Database administrators use the Utility Control Point and Utility Explorer in
SQL Server Management Studio to centrally manage and monitor data-tier applications at scale.
Common Uses for Data-Tier Applications
Data-tier applications are used in a multitude of ways to serve many different needs. For
example, organizations may use data-tier applications when they need to
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Deploy a data-tier application for test, staging, and production instances of the Data-
base Engine.
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Create DAC packages to tighten integration handoffs between data-tier developers
and database administrators.
■
Move changes from development to production.
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Upgrade an existing DAC instance to a newer version of the DAC by using the Upgrade
Data-Tier Wizard.
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Compare database schemas between two data-tier applications.
■
Upgrade database schemas from older versions of SQL Server to SQL Server 2008 R2—
for example, to extract a data-tier application from SQL Server 2000 and then deploy
the package on SQL Server 2008 R2.
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Consider next generation development, which is achieved by importing an existing
version of a DAC into Visual Studio and then modifying the schema, objects, or de-
ployment strategies.
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Author database objects by using source code control systems such as Team
Foundation Server.
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Integrate data-tier applications with Microsoft SQL Azure. Currently, it is possible to
deploy, register, and delete. Upgrading of data-tier applications with SQL Azure is
likely to be supported in future releases.