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= Data-Access Layer

The data-access layer is responsible for all outgoing connections to access and process data. This is mainly about accessing data from a persistent data-store. External system could also be accessed from the data-access layer if they match this definition, e.g. a mongo-db via rest services.

== Database

You need to make your choice for a database. Options are documented https://github.com/devonfw/devonfw-guide/blob/master/general/db/guide-database.asciidoc[here].

The classical approach is to use a Relational Database Management System (RDMS). In such a case, we strongly recommend to follow our link:guide-jpa[JPA Guide]. Some NoSQL databases are supported by https://spring.io/projects/spring-data[spring-data] so you can consider the link:guide-repository[repository guide].