Module 18: BW/4HANA & CDS Views (BW/4HANA 2.0)
Core Data Services (CDS) are a key modeling paradigm in SAP HANA and S/4HANA.
In BW/4HANA, CDS is not a replacement for BW modeling objects — it is a complementary semantic layer.
This module covers:
- CDS basics for BW
- CDS vs BW models
- Analytical CDS views
- BW Query on CDS
- When to use CDS instead of BW objects
1. CDS Basics for BW
1.1 What is CDS?
Core Data Services (CDS) is:
- A SQL-based data modeling language
- Executed directly in SAP HANA
- Used for semantic-rich data models
CDS supports:
- Associations
- Annotations
- Authorization checks
- Analytical semantics
Database Tables → CDS View → Consumption
1.2 CDS in BW Context
In BW/4HANA, CDS can be used:
- As a data source (via Open ODS View)
- As an analytical provider
- As a semantic abstraction layer
BW remains the enterprise data warehouse; CDS provides modeling agility.
2. CDS vs BW Models (Critical Comparison)
Conceptual Difference
| Aspect | CDS | BW Models |
|---|---|---|
| Purpose | Semantic modeling | Enterprise DW |
| Persistence | No | Yes (aDSO) |
| History | Limited | Full |
| Delta handling | Limited | Robust |
| Governance | Medium | Strong |
Functional Difference
| Feature | CDS | BW |
|---|---|---|
| Pushdown | Native | Native |
| Authorizations | DCL | Analysis auth |
| Reporting | Yes | Yes |
| Planning | No | Yes |
| Process chains | No | Yes |
CDS is model-centric; BW is process-centric.
3. Analytical CDS Views
3.1 What are Analytical CDS Views?
Analytical CDS views:
- Are annotated for analytics
- Support measures and dimensions
- Can be consumed by analytics tools
Example annotations:
@Analytics.dataCategory: #CUBE
@Analytics.query: true
Use Cases
- Embedded analytics in S/4HANA
- Real-time operational reporting
- Lightweight analytics
Analytical CDS views do not replace BW Queries for enterprise analytics.
4. BW Query on CDS Views
How BW Consumes CDS
BW can consume CDS via:
- Open ODS Views
- HANA source systems
- BW Queries on top
CDS View → Open ODS View → CompositeProvider → BW Query
Benefits
- Reuse S/4HANA semantics
- Reduce data duplication
- Enable hybrid analytics
Use BW Query to add enterprise semantics and authorizations.
5. When to Use CDS Instead of BW Objects
Use CDS When:
- Data is operational and real-time
- No historical tracking is required
- Data volume is manageable
- You are in S/4 Embedded Analytics
Use BW Objects When:
- Historical analysis is needed
- Data is sourced from multiple systems
- Delta handling is complex
- Planning or write-back is required
CDS for operational insight, BW for enterprise analytics.
6. Hybrid BW + CDS Architecture (Real Projects)
S/4HANA
↓
CDS Views (Operational Semantics)
↓
Open ODS Views
↓
BW CompositeProviders
↓
BW Queries
↓
SAC / AO
7. BW/4HANA 2.0 vs BW/4HANA 1.0 (CDS Usage)
| Aspect | BW/4HANA 1.0 | BW/4HANA 2.0 |
|---|---|---|
| CDS adoption | Limited | Strong |
| Integration | Optional | Strategic |
| Federation | Basic | Advanced |
8. Common Misconceptions
"CDS will replace BW"
"BW Queries are obsolete"
"CDS authorizations work everywhere"
9. Interview-Grade Questions
Q1. Can BW Queries run directly on CDS?
Answer: Yes, via Open ODS Views or HANA source systems, but BW semantics and authorizations still apply at the BW layer.
Q2. CDS vs BW — which is better?
Answer: They serve different purposes. CDS is ideal for operational analytics, while BW is designed for enterprise-scale, historical analytics.
10. Summary
- CDS complements BW, not replaces it
- Analytical CDS is ideal for embedded analytics
- BW adds governance, history, and automation
- Hybrid architectures are common
- Correct choice depends on use case
11. What's Next?
➡️ Module 19: Integration Scenarios & Source Systems
Use CDS for speed, BW for scale and control.