Introducing CDS Views – ABAP Dictionary Views, HANA CDS & ABAP CDS for data modeling
Data models are an essential tool in building applications. They are created by using tables or views. Tables, on the other hand, are objects in databases that hold content (store information), while views collect data from already existing tables, allowing users to select the right rows and columns from the original tables without copying the content, therefore using fewer data.
Models bring consistency in defining and formatting database content across systems. They enable multiple applications to share the same data, which lowers development costs, reduces time-to-market, and improves quality & performance.
ABAP Dictionary Views is one of the first data modeling tools in the SAP environment. It’s relatively easy to apply and enables users to define database entities on the application server. However, it has some limitations and offers fewer features than those presented below.
Another solution is HANA CDS, which was developed together with SAP HANA. This approach allows users to create models directly in the database without using an application server. With HANA CDS, you can run more data operations than with ABAP Dictionary. We outline the differences between these tools in the table below.
Source: SAP Blogs
ABAP CDS is the last solution analyzed in our overview. It’s very similar to HANA CDS, which means that it gives users similar results. However, both tools offer varied features.
ABAP CDS is available on the application server, allowing using this tool with different databases, which means this solution provides universal features that exist in all SQL databases, ex. Oracle Database, PostgreSQL, SAP HANA, and others. HANA CDS is used exclusively with the SAP HANA database and therefore offers features designed for HANA and not available in ABAP CDS. However, work is underway to implement them into ABAP CDS. ABAP itself has been equipped with features, such as client support and table caching, that aren’t available in HANA CDS.
|ABAP CDS and HANA CDS differences|
|ABAP CDS||HANA CDS|
|Same semantics across all databases||Semantics only for SAP HANA (special features available)|
|Focus on building views||Focus on building models from scratch|
|Integration with ABAP Dictionary|
Considering these conclusions, SAP’s Core Data Services solutions provide a single concept for data modeling, implemented in SAP HANA and on the ABAP application server. The design guidelines are the same for both deployments, and due to working in various environments – we can notice how they differ.
- On 07/12/2022