In OutSystems, an Entity Identifier must meet which requirement?

In OutSystems, the requirement that an Entity Identifier can only be a single attribute is correct because the Entity Identifier is designed to provide a unique key for each record in an entity. This uniqueness ensures that each instance of the entity can be distinctly identified and accessed.

Typically, having a single attribute as the identifier simplifies operations like querying, updating, and deleting records. While it is possible to create a composite key using multiple attributes for identifying records in some databases, OutSystems specifically encourages the use of a single attribute for entity identifiers to maintain consistency, ease of use, and performance.

The focus on a single attribute helps developers avoid complexities that can arise with composite keys, such as difficulties in referencing or establishing relations with other entities. Consequently, this design choice aligns with best practices in database design and usability within the OutSystems platform.