A Comprehensive Guide to SAP CDS Views

Srinivas Marija

A Comprehensive Guide to SAP CDS Views

SAP Core Data Services (CDS) Views are an integral part of modern SAP development. They provide a powerful framework for data modeling and data processing in SAP's in-memory database, SAP HANA. CDS Views enable developers to define and consume data models efficiently and serve as the foundation for various SAP solutions, including SAP S/4HANA and SAP Fiori. This article delves into the basics, benefits, and use cases of CDS Views.

What Are SAP CDS Views?

SAP CDS Views are a declarative framework for defining and managing data models at the database level. They are designed to work seamlessly with SAP HANA and other databases, allowing developers to create data models that can be reused and consumed in different applications.

CDS Views are written using a SQL-based syntax and are defined in the ABAP Development Tools (ADT) within Eclipse or SAP Business Application Studio. They extend the capabilities of traditional database views by incorporating additional functionalities like annotations, associations, and expressions.

Key Features of CDS Views

1. Declarative Modeling: CDS Views enable developers to define data models using a high-level, SQL-based syntax. This declarative approach simplifies the design process and improves readability.
2. Annotations: Annotations provide metadata that enrich CDS Views with additional information, such as user interface (UI) attributes, analytical tags, and performance optimization hints.
3. Associations: CDS Views support associations, which are similar to joins in SQL but are defined as reusable relationships between data entities. Associations improve modularity and maintainability.
4. Hierarchical Data Modeling: CDS Views allow developers to model hierarchical relationships, making it easier to represent complex data structures.
5. Integration with Fiori and Analytics: CDS Views can be used to define data sources for SAP Fiori applications and analytical dashboards, ensuring seamless integration across the SAP ecosystem.
6. Performance Optimization: CDS Views are processed at the database level, leveraging SAP HANA’s in-memory computing capabilities for high performance.

Types of CDS Views

CDS Views can be categorized based on their primary use cases:

1. Basic Views: These are foundational views that fetch data from database tables or other CDS Views. They serve as building blocks for more complex views.
2. Composite Views: Built on top of basic views, composite views combine multiple data sources to provide aggregated or derived data.
3. Consumption Views: These views are designed to be consumed by applications, such as SAP Fiori or analytics tools. They include annotations and are optimized for specific use cases.

How to Create a CDS View

1. Setup: Open ABAP Development Tools (ADT) in Eclipse or SAP Business Application Studio.
2. Create a CDS View:Right-click on a package in the ABAP repository and select New > Other > Data Definition,Provide a name and description for the CDS View.
3. Define the Data Model: Use the @AbapCatalog and @EndUserText annotations to define the view. Specify the data source and structure using the SELECT statement.

@AbapCatalog.sqlViewName: 'ZDEMO_CDS'

@EndUserText.label: 'Demo CDS View'

define view ZDEMO_CDS as select from my_table {

key id,

name,

created_at

}

4. Activate the View: Save and activate the CDS View. This makes it available for consumption in applications.

Benefits of Using CDS Views

1. Simplified Data Modeling: CDS Views allow developers to model complex data structures without extensive coding.
2. Reusability: Once created, CDS Views can be reused across multiple applications, reducing redundancy.
3. Enhanced Performance: By executing logic at the database level, CDS Views leverage SAP HANA’s speed and efficiency.
4. Seamless Integration: CDS Views integrate well with SAP Fiori, ABAP programs, and SAP analytics solutions.
5. Future-Proof: As a central component of SAP's data modeling strategy, CDS Views align with the shift towards SAP S/4HANA.

Use Cases of CDS Views

1. Reporting and Analytics: CDS Views are widely used to create data models for analytical dashboards and reports.
2. SAP Fiori Applications: They serve as back-end data providers for SAP Fiori elements like lists, charts, and forms.
3. Data Transformation: CDS Views can transform raw data into meaningful insights by applying filters, calculations, and aggregations.
4. Authorization and Security: Developers can define authorization checks directly within CDS Views using annotations.

Difference between ABAP CDS views and HANA CDS Views

The terms ABAP CDS Views and HANA CDS Views both refer to Core Data Services (CDS) used for data modeling within the SAP ecosystem, but they differ significantly in their purpose, environment, and features. Here's a detailed comparison:

1. Platform and Development Environment

ABAP CDS Views:

• Developed and run within the ABAP layer of SAP systems.
• Managed using ABAP Development Tools (ADT) in Eclipse or SAP Business Application Studio.
• Primarily used for data modeling in ABAP-based systems, such as SAP S/4HANA or SAP ECC.
• Part of the ABAP programming model, focusing on integration with ABAP and SAP Fiori.

HANA CDS Views:

• Created and executed at the database level directly in SAP HANA.
• Developed using SAP HANA Studio or SAP Web IDE.
• Utilized primarily for native SAP HANA applications and advanced analytics, providing deep database-level capabilities.
• Focuses on leveraging native HANA features like calculation engines and sophisticated optimizations.

2. Language and Syntax

ABAP CDS Views:

• Use ABAP CDS language, which is a part of the ABAP Core Data Services syntax.
• Can include annotations for ABAP-specific functionalities, such as defining UI semantics for SAP Fiori or specifying authorization checks for ABAP programs.
• Integrate directly with ABAP-based services and programs, making them highly integrated within the SAP ABAP stack.

HANA CDS Views:

• Use HANA SQLScript and native HANA CDS syntax within the SAP HANA environment.
• Offer database-native functionalities and allow access to advanced HANA features, such as text analysis, spatial processing, and predictive capabilities.
• Typically do not directly integrate with ABAP semantics but rather focus on database-centric operations and transformations.

3. Purpose and Use Cases

ABAP CDS Views:

Designed for ABAP-based data modeling and can be consumed by ABAP reports, SAP Fiori apps, and analytical queries.

• Useful for business logic integration, user interface definition, and access control management (via annotations).
• Can include OData exposure easily, which is often used for SAP Fiori applications and web services.

HANA CDS Views:

• Focus on database-native modeling and processing that require complex transformations or calculations optimized at the database level.
• Suited for real-time analytics and large-scale data processing tasks within HANA.
• Used for scenarios requiring performance-intensive operations and deep HANA-native capabilities.

4. Features and Capabilities

ABAP CDS Views:

• Support ABAP-specific annotations like @EndUserText, @UI, and @AccessControl.
• Offer seamless integration with ABAP programs, services, and existing ABAP infrastructure.
• Provide hierarchical and complex relationships within ABAP environments.

HANA CDS Views:

• Support advanced data processing features like graph analysis, text mining, and geospatial processing.
• Allow the definition of complex calculations directly at the database layer, leveraging HANA's in-memory processing.
• Offer extensive performance optimizations that are not bound by ABAP layer constraints.

5. Deployment and Execution

ABAP CDS Views:

• Deployed and executed within the ABAP server context.
• Primarily intended for business logic layer and end-user applications.

HANA CDS Views:

• Deployed and executed directly within the SAP HANA database.
• Intended for database logic and high-performance analytical operations.

Summary

• ABAP CDS Views are tightly integrated with the ABAP stack and intended for business applications, user interfaces, and authorization checks.
• HANA CDS Views operate at the database level and are geared toward native HANA functionalities and complex analytics.

Conclusion

SAP CDS Views are a cornerstone of modern SAP development, offering a robust framework for data modeling, performance optimization, and seamless integration. Their ability to simplify complex data scenarios while enhancing performance makes them invaluable for developers working within the SAP ecosystem. By adopting CDS Views, organizations can unlock the full potential of SAP HANA and build future-ready applications with ease.