Databaselaag

Databaselaag is an architectural layer in software applications responsible for persisting and retrieving data. It provides an abstraction over storage technologies, allowing the rest of the application to operate without direct knowledge of the underlying database.

The databaselaag typically exposes create, read, update and delete operations for domain entities, and handles tasks such as query generation, mapping between domain models and database schemas, connection management, and transaction handling.

Common patterns include the repository pattern, which presents a collection-like interface to domain objects, and data mapper or active record variants that control how objects are persisted. Object-relational mappers (ORMs) may be used to automate mapping, while raw SQL remains possible for performance-sensitive paths.

Databaselaag interacts with various storage technologies, including relational databases (SQL) and NoSQL stores. It also concerns security—such as parameterized queries and least-privilege access—data integrity, migrations, versioning, caching, and monitoring of query performance and error handling.

In layered architectures, the databaselaag is kept separate from business logic and presentation layers to promote separation of concerns, testability and scalability. The exact structure varies by technology stack and design goals, balancing abstraction with the need for direct data access when appropriate.