Subject: SAP-HANA-Live
SAP HANA Live leverages Core Data Services (CDS) views to provide real-time operational reporting on top of the HANA database. While CDS views offer a powerful abstraction layer for data modeling, performance challenges arise when dealing with complex, nested, or large-volume CDS models. Ensuring optimal performance in such scenarios is critical for delivering responsive analytics and reducing system load.
This article outlines key strategies and best practices for optimizing the performance of complex CDS views in an SAP HANA Live environment.
CDS views in SAP HANA Live often involve:
As CDS views grow in complexity, so does the cost of query execution. Inefficient design may lead to slow report rendering, increased memory usage, and potential performance bottlenecks on the HANA database.
Avoid over-nesting of CDS views. While layering views promotes reusability and abstraction, excessive dependency chains can increase the query execution time. Use base views (Interface Views) for reusable logic, but design Consumption Views with performance in mind.
Tip: Use
ST05SQL trace or HANA PlanViz to analyze execution plans of nested CDS queries.
CDS associations should be used with left outer join semantics only when necessary. Unfiltered or unused associations in the SELECT list or WHERE clause can lead to full table scans.
Best Practice: Define associations with
@ObjectModel.foreignKey.associationannotations, but avoid resolving them unless required by the consumer.
Apply filters as early as possible in the CDS hierarchy to reduce data volumes passed between views.
parameterized views to enforce mandatory filters (e.g., for company code, fiscal year).Complex calculations (e.g., nested case statements, arithmetic operations) should be minimized or offloaded to:
Use SQL functions like COALESCE, NULLIF, and CASE judiciously and avoid redundant computations.
In intermediate views, use projections to select only the necessary fields rather than selecting all (SELECT *). This reduces memory usage and improves HANA engine efficiency.
Repeated aggregations in nested CDS views can be expensive. Try to:
Use GROUP BY only when required, and ensure it aligns with the intended granularity.
Annotations guide the behavior of CDS views in analytical and UI contexts. Optimize by:
@Analytics.query: true only if they are used for reporting@AccessControl.authorizationCheck: #NOT_REQUIRED if access control is handled elsewhere@VDM.viewType to differentiate base/interface/consumption viewsAlthough CDS views are virtual and do not store data, their performance depends on underlying table structures.
SAP offers several tools for CDS performance monitoring:
Performance optimization of complex CDS views in SAP HANA Live is both an art and a science. By applying structured design principles, leveraging system tools, and adhering to SAP’s recommended best practices, organizations can significantly enhance the responsiveness and efficiency of their reporting solutions.
As the reliance on real-time analytics grows, so does the importance of well-optimized CDS views. A thoughtful and performance-conscious approach to CDS development is essential for long-term success in any HANA Live implementation.