ATG’s Data Anywhere Architecture (DAA) gives developers a single API, called the Repository API, for using data resources in their applications. Behind the Repository API, DAA insulates and abstracts application developers from the specifics of the data source, so much so that the nature of the underlying data source may completely change without major impact. For example, customer data may reside in a SQL/JDBC database today, but will move to an LDAP directory in the future. DAA could handle this without having to touch any code within the application.
With the ATG Data Anywhere, the application logic created by developers uses the same approach to
interact with data regardless of the source of that data. One of the most powerful aspects of this
architecture is that the source of the data is hidden behind the ATG Repository abstraction. It is easy to
change from a relational data source to an LDAP directory as none of the application logic needs to
Please see the following link, it describes more about data anywhere architecture.
In simple words to say Data anywhere architecture means suppose you are using MySql as database now and tomorrow Client say that we need MS Sql server as database . so without touching any code you can transfer your data to MS Sql server database without any worries. just you have to do One line change in the properties file . Its done. You can check to data being populated into MS Sql server. How its is done? Its ORM(Object relational mapping ).we have a sql repository which is a logical view of data stored in a relational database which will take care of it.