---
parser: v2
primary_tag: topic>abap-development
tags: [  tutorial>beginner, topic>abap-development, topic>abap-extensibility ]
time: 15
slug: abap-extensibility-custom-code-list
canonical_url: https://developers.sap.com/tutorials/abap-extensibility-custom-code-list
---

# S/4HANA ABAP Extensibility - Custom Code List
<!-- description --> Create a custom CDS view from an existing data source and expose it as a Web Service.

## Prerequisites  
The Prerequisites for the usage of CDS Views is the assignment of the Business Catalog **`SAP_CORE_BC_EXT`** to your user.
Your user needs to assign Business Catalog **`SAP_CORE_BC_COM`** to be able to use the Communication Management Application, your user needs Business Catalog **`SAP_CORE_BC_COM`**.

## You will learn  
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### Open Custom Business Object Application

Navigate to the **Extensibility** category and press the **Custom Business Object** tile to start the application.