In SAP HANA Extended Application Services Advanced Model (HANA XSA), CDS (Core Data Services) views are an essential part of data modeling and data access. CDS views provide a semantic layer on top of the underlying database tables, enabling developers to define and manipulate complex data structures.
Here are some key points about CDS views in HANA XSA:
CDS View Definition: CDS views in HANA XSA are defined using the CDS syntax, which allows developers to define entities, associations, projections, and other constructs to represent the data model. CDS views can be created using the CDS Editor in the SAP Web IDE for SAP HANA or through other development tools.
Data Modeling Capabilities: CDS views in HANA XSA support various data modeling capabilities, such as defining calculated fields, aggregations, joins, filters, and sorting. Developers can leverage these capabilities to create comprehensive and efficient data models that meet the requirements of their applications.
Reusability: CDS views in HANA XSA can be reused across different applications and scenarios. They provide a modular approach to data modeling, allowing developers to build upon existing views and combine them to create more complex views as needed. This reusability promotes consistency, reduces redundancy, and simplifies maintenance.
Annotations and UI Annotations: CDS views support annotations, which are metadata attributes used to enrich the semantic understanding of the data model. Annotations can be used to define data validation rules, labels, descriptions, and more. Additionally, UI annotations enable the creation of user interfaces based on CDS views, allowing developers to design user-friendly applications.
Authorization and Security: CDS views in HANA XSA inherit the authorization and security settings from the underlying database tables. Developers can define access control and data-level security using roles and privileges, ensuring that the data is protected and accessible only to authorized users.
Consumption in Applications: CDS views can be consumed by various application development frameworks and tools in HANA XSA, such as SAPUI5, Node.js, Java, and XSJS services. The CDS views act as a data source for these applications, enabling developers to fetch and manipulate the data efficiently.
Performance Optimization: HANA XSA provides performance optimization techniques for CDS views, such as the creation of database indexes, partitioning, and materialized views. These techniques help optimize query performance and improve the overall responsiveness of the applications.
It's important to note that specific implementation details and capabilities may vary based on the version of SAP HANA XSA and the development tools being used. It's recommended to refer to the official SAP documentation and consult with the SAP experts to get the most up-to-date and accurate information regarding CDS views in HANA XSA.