Let’s start with the definition of SAP CDS Views. CDS is short for Core Data Services. It is a rich and user-friendly programming language that has been developed by SAP. Users can define and consume models on the database with SAP CDS View without going through the application server. Moreover, CDS Views are widely acknowledged to be a very advanced and optimized platform for creating data models with the help of OData services that can be transferred outside the applications.
Data models on SAP CDS are not based on application servers as is traditional but on database servers. The need for real-time performance by organizations is also met by SAP CDS, a data modeling framework, by leveraging the strong in-memory database of SAP HANA. This is done by optimizing operations at the level of the database resulting in a lowering of application execution time along with quick retrieval of databases. Users can access UI and SAP CDS Views through data models that are presented by application servers through SAP CDS. Views can be created in SAP CDS as design-time files in the storage repository with the SAP HANA Extended Application Services (SAP HANA XS).
The Origins of SAP CDS Views and its Evolution
SAP CDS Views was first introduced by SAP as a programming model. Launched as a virtual data model, it came out of the box with SAP HANA and allowed quick and direct access to all the basic tables of the SAP HANA database. The objective of SAP is to permit logic from the application server to the client-side database named ‘Code-to-Data’ or ‘Code Pushdown’ that is then extracted by the SAP CDS Views from the ABAP applications to be executed on the database.
SAP has been instrumental in revolutionizing the way that applications are developed and data is managed. It has more than met the expectations of organizations of carrying out as many operations as possible at the database level by ensuring fast and real-time performance through its in-memory database. In the past, the norm had been to use an application server rather than a database server for database modeling. With the evolution of SAP HANA and all the advantages it brings to the table, the present norm is to use data modeling at the database level with the help of Core Data Services (CDS), popularly termed SAP CDS Views.
The Various Functionalities of SAP CDS Views
Most organizations have one thing in common and that is to carry out real-time data reporting and analytics on transactional data. This has become a reality now as, supported by the power of HANA, it is possible to do large queries (analytics) on S/4 HANA without needing a separate data warehouse or facing any lack or degradation in performance. VDMs (Virtual Data Models) can be created directly in ERP with SAP CDS Views to be used as high-performing front-end tools.
SAP S/4 HANA Embedded Analytics which has many cutting-edge analytical features is in-built into SAP CDS Views and may be used for real-time data analytics on live transactional data even without determining the underlying tables/structures. These views may either be used to create new data models directly or combined with both enhanced and modified new views.
SAP HANA XS (SAP HANA Extended Application Services) permits users to define a view in an SAP CDS Views document. This can be stored as design-time files in the repository and read by applications specifically developed for this purpose. Further, these repository files having view definitions can be moved to other SAP HANA systems like a delivery unit.
Once committed to the repository, all changes made to the repository version of the file are visible. An example is an application that refers to the design-time version of a view from the repository instead of a runtime view in the catalog. This is reflected in the repository file and users do not have to wait for the activation of a runtime version of the view by the repository.
After a CDS document is activated, there is a corresponding generation of a catalog object for each object as defined in the document. The specific type of object generated however determines the precise location of the catalog. For instance, for SAP CDS Views definition, the corresponding catalog object in SAP HANA XS classic is generated in the location <SID> Catalog <MYSCHEMA> Views.
The Various Benefits of SAP CDS Views
The following are some of the main benefits of SAP CDS Views.
Computing and calculations are done directly on the database layer instead of the application server since SAP CDS Views is a code-to-data technology in ABAP.
All features of SAP CDS Views are also available outside the SAP native applications as they are less conventional in SE11 views.
Support for inner join, cross join, full join, outer join, and right outer join are provided by CDS Views.
Aggregation and Numeric functions as well as automatic client handling are supported by SAP CDS Views
Since SAP works independent of the database, CDS View on SAP can be operated on any database platform supported by SAP.
CDS automatically supports all client operations as it can publish ODATA service annotations directly from SAP CDS Views.
These are some of the main benefits of SAP CDS Views.
The Types of SAP CDS Views
SAP CDS Views are of two types - HANA CDS Views and ABAP CDS Views. In the past, there were only SAP CDS Views in the SAP HANA ecosystem but currently, SAP NetWeaver also has CDS as ABAP, helping developers to work with the ABAP programming layer outside the execution layer that is allotted to the database.