Which expressions must be given an alias in a core data services (CDS) View?

In the context of core data services (CDS) Views, certain expressions, including unit conversions, are required to be given an alias. An alias provides a clearer naming convention for derived fields, which enhances the readability and usability of the CDS View.

Unit conversions often produce results with changing dimensions or formats that may not correspond neatly to existing fields in the database. By assigning an alias to the result of a unit conversion, the CDS View ensures that the output is clear and understandable to users who may not be proficient in interpreting the underlying calculations immediately.

This practice is essential in managing complex data models where multiple transformations might be applied, and clarity about the output is critical for downstream use, such as reporting or data analysis. Having an alias for unit conversion results streamlines the data handling and improves overall data governance within the CDS framework.

Other types of expressions—like cast expressions, aggregated values, and nested functions—have different handling rules in terms of naming and do not necessarily require an alias for proper operation within CDS Views.