In the Context of SAP HANA Live
Core Data Services (CDS) Views are a powerful tool in SAP HANA Live environments, enabling real-time access to transactional data with rich semantic modeling. However, like any complex data artifact, CDS Views can sometimes produce unexpected results or performance issues, making debugging an essential skill for SAP developers and consultants.
This article explores various methods and tools for debugging CDS Views, helping you identify and resolve issues efficiently within SAP HANA Live scenarios.
¶ Understanding the Challenge of Debugging CDS Views
Unlike traditional ABAP programs, CDS Views are defined declaratively and run directly in the SAP HANA database layer. This means:
- You cannot debug CDS Views using classical ABAP debuggers.
- CDS Views do not have procedural code, so typical breakpoints don’t apply.
- Debugging mainly involves tracing the data flow, checking SQL generation, and analyzing performance.
Therefore, the debugging approach focuses on inspection, analysis, and profiling rather than line-by-line code stepping.
Before diving into debugging methods, here are typical issues developers encounter:
- Unexpected or incorrect data results (wrong joins, filters).
- Performance bottlenecks (slow queries).
- Incorrect or missing annotations causing UI or analytical issues.
- Authorization or data access problems.
- Syntax or activation errors in CDS definitions.
CDS Views are ultimately translated into SQL statements executed on SAP HANA. Reviewing this SQL helps to verify joins, filters, and projections.
- In ABAP Development Tools (ADT) (Eclipse), right-click the CDS view → Open SQL View or Show SQL Preview.
- In SAP HANA Studio or Web IDE, you can also generate and analyze the SQL code.
- Run the generated SQL directly on SAP HANA database to test the results and debug data issues.
Although CDS Views run in HANA, if called from ABAP, you can enable SQL Trace (transaction ST05) to capture the executed SQL and analyze performance.
- Activate SQL Trace.
- Execute the transaction or report calling the CDS view.
- Review the SQL statements, execution time, and possible bottlenecks.
For performance issues on the ABAP side, SAT (Runtime Analysis) helps identify expensive calls and inefficient data fetches.
PlanViz is the best tool to analyze the execution plan of CDS Views on SAP HANA.
- Run your CDS View’s SQL directly in SAP HANA Studio or Web IDE.
- Launch PlanViz to see detailed query execution plans.
- Identify expensive operations like full table scans, large joins, or missing indexes.
- Optimize CDS view definitions or underlying database objects based on findings.
¶ 4. Activate and Use Trace in ABAP Layer
For CDS Views exposed as OData services or consumed in Fiori apps, you can:
- Enable Gateway error logs and trace.
- Use /IWFND/TRACES for OData service traces.
- Check error messages related to annotations or authorization failures.
¶ 5. Verify CDS View Syntax and Annotations
Syntax errors or incorrect annotations can cause activation failures or runtime errors.
- Use the ABAP Development Tools syntax checker.
- Validate the correctness of annotations, especially those related to OData exposure or UI.
- Check dependencies and associations for consistency.
- Start small: Test individual components and simple projections before complex joins or calculations.
- Use explicit filters: Limit data in test queries to isolate issues.
- Check join cardinality: Incorrect join conditions cause data duplication or loss.
- Validate associations: Ensure associations are defined correctly and used properly.
- Monitor performance continuously: Use PlanViz to prevent performance degradation.
- Leverage SAP Notes and Documentation: SAP regularly updates troubleshooting guides and patches.
Debugging CDS Views requires a blend of tools and techniques given their declarative nature and execution in the SAP HANA layer. By mastering SQL inspection, execution plan analysis, and trace tools, developers can effectively troubleshoot data issues and optimize performance within SAP HANA Live environments.
Understanding how CDS Views interact with the underlying HANA database and SAP application layers is key to successful debugging and delivering efficient, reliable real-time analytics.