What is SAP OData V4?

SAP OData V4 is a modern standard for communication between SAP systems and external applications.

The interface protocol scores above all with its performance, flexibility and diverse query options. It is even suitable for complex data models.

SAP OData V4 is the latest version of the Open Data Protocol (OData) within the SAP product portfolio. It was published in 2014.

It is a standardised REST-based interface for providing business-relevant data from SAP systems. The aim is to provide business logic data models efficiently, transparently and in real time via web protocols.

OData V4 in SAP follows the OASIS standard and is fully compatible with JSON as the main format. Integration takes place both in the classic ABAP stack and in modern SAP S/4HANA environments. The Open Data Protocol V4 can be used across all platforms - both on-premise and in the cloud. This makes OData V4 the ideal interface for hybrid SAP landscapes.

Yes, SAP OData V4 is a web service. More precisely, it is a REST-based web service that works via the HTTP internet protocol.

It provides SAP data as so-called "resources" that users can call up, create, change or delete in a targeted manner. OData V4 uses modern web standards to exchange data easily and efficiently. This is often done in JSON format, which is particularly suitable for web applications.

OData stands for Open Data Protocol. It was originally developed by Microsoft and later established as an open standard. SAP uses OData primarily to exchange data between the SAP system and modern user interfaces - such as Fiori apps.

The special thing about OData is that it enables SAP data to be retrieved or changed via the HTTP internet protocol. The data accesses follow a fixed pattern - similar to calling up a website. This method is based on so-called REST principles, which are very common in modern web development.

OData can be used to perform the following typical tasks, for example:

• Read data (for example, display customers)
• Create data (for example, create a new order)
• Change data (for example, update customer data)
• Delete data

As an example, an OData call could look like this:

https:// example.com /odata/v4 /BusinessPartners?$select = Name,Email&$filter= Country eq ‘DE’

This call specifically queries the names and email addresses of business partners from Germany. Such an approach saves data volume and speeds up the query.

The response from the system usually comes in JSON format - a compact and readable data format that is particularly suitable for web applications.

Another advantage: OData also provides metadata. This is information about which data is available, how it is structured and what can be realised with it. This metadata helps developers or systems such as SAPUI5 to automatically connect to the service and generate customised user interfaces.

SAP OData V4 is designed to support complex business data models. It utilises nested data structures (so-called complex types) and allows the representation of relationships between data objects via navigation properties. One example of this is parent-child relationships between customers and their orders.

A major advantage is the extensive support for targeted queries with filters and selections. For example, the following conditions can be formulated:

• $filter=Amount gt 1000 and Status eq 'Open'
• $select=CustomerName,OrderDate
• $expand=Items($select=ProductID,Quantity)

This means: Orders with an amount over 1000 and the status "open" are selected. Only the customer name and order date fields are returned. The order items with article number and quantity are also included.

Such filter and selection options significantly reduce the amount of data transferred and thus relieve the strain on system resources. OData V4 also supports so-called actions. These are user-defined functions that can be applied directly to entities (data objects), for example to authorise an order.

In addition, functions such as $count, $orderby or $top enable data records to be counted, sorted and limited. This allows large volumes of data to be analysed efficiently and in a targeted manner via the interface.

OData V4 services are managed in SAP using specific transactions that differ from those for OData V2. A distinction is made here between frontend and backend.

Transaction /IWBEP/V4_ADMIN is used in the backend system (SAP Gateway Backend). It is used to register and manage OData V4 services. Services can be created here, service groups defined and the associated model and data provider classes (MPC and DPC) assigned.

In the front-end system (SAP Gateway Hub), on the other hand, transaction /IWFND/V4_ADMIN is used. It enables service groups to be published, system aliases to be assigned and the routing configuration to be carried out. It also allows access to support tools such as the SAP Gateway Client and the error log.

Developers can also use transaction /IWFND/GW_CLIENT to test OData services. Developers can send specific HTTP requests such as GET or POST to a service, set parameters and analyze the response directly. It is therefore ideal for debugging and quickly testing individual endpoints.

The difference between OData V2 and OData V4 is considerable.

OData V2 was already a solid version, but OData V4 brought numerous improvements:

• JSON is the preferred format (V2 often used Atom/XML)
• better support for actions and functions
• improved filter options with logical and arithmetic operators
• more precise metadata description
• Support for delta queries to increase efficiency with frequent requests

V4 is therefore more performant, more standard-compliant and better suited to modern web technologies. In the SAP world, this leads to better SAPUI5 applications and more efficient backend communication.

In addition, OData V4 has a modular structure and enables individual features to be implemented independently of each other. This creates greater flexibility in the design of services and supports best practices in API development.

SOAP (Simple Object Access Protocol) and OData follow different philosophies.

• SOAP is a comprehensive protocol that uses XML and is often used in complex, transaction-based business processes. It requires a so-called WSDL (Web Services Description Language) to describe the service.
• OData, on the other hand, is leaner, based on REST and works with JSON. It does not use any additional protocols, only HTTP. In practice, OData is easier to integrate, requires less additional effort and is better suited to modern web and cloud applications.

While SOAP relies on strong typing and comprehensive security mechanisms, OData focuses on simple integration, flexibility and extensibility. In many modern architectures where fast development cycles and UI integration are required, OData is therefore the preferred choice.

OData is a special type of REST API. Both use the HTTP protocol to exchange data.

The main difference: REST is a general principle for web services. OData, on the other hand, is a defined standard protocol that describes exactly how data can be structured and queried.

OData therefore comes with clear rules and functions such as filters, sorting or metadata, which REST APIs do not necessarily have. This often makes OData easier to use when complex data models are involved.

SAP OData V4 has numerous advantages for the development of SAP applications. The main ones are

• standardized interfaces for business data that always work the same way
• fast data access thanks to targeted filter and selection options
• clear structure thanks to groups of data, links between them and special functions
• optimal integration into SAP Fiori and SAPUI5 interfaces
• support for additional information (annotations) that help to automatically optimize user interfaces
• less programming effort thanks to simple modeling with CDS and ABAP
• data is transferred in easy-to-use JSON format

These advantages lead to a higher degree of reusability and maintainability of code. Developers can quickly adapt existing services and integrate them into new applications.

There are also synergies with other SAP technologies, such as the Business Technology Platform (BTP), which can seamlessly access OData V4 services. Low-code/no-code tools also benefit from the clear structure and automation provided by OData V4.

Switching to SAP OData V4 not only makes sense, but is even necessary in the long term. Although OData V2 is currently still supported, many new functions are only being developed in V4.

Version 4 also has clear advantages in terms of performance, maintainability and expandability. Companies converting to SAP S/4HANA or developing SAP Fiori applications benefit directly from the corresponding options.

The strength of OData V4 compared to the previous version is particularly evident in complex filter requests and the use of actions to map individual business logic.

In addition to the functional advantages, there are also strategic reasons for the changeover: SAP's long-term roadmap relies heavily on modern interfaces that enable cloud compatibility, scalability and a high level of automation. All of this can be realized much better with OData V4.

In SAP S/4HANA, OData V4 is primarily used to make business data and processes accessible via modern interfaces. Developers model the data and business rules with CDS views and use the ABAP RESTful Application Programming Model (RAP), which automatically generates OData V4 services.

These services enable applications such as SAP Fiori to easily and efficiently access and edit data or map complex processes. This reduces development times and errors. At the same time, the interfaces remain flexible and expandable.

In the SAP Cloud Platform, SAP OData V4 is used via the SAP Business Application Studio. OData V4 services can be created, provided and tested here. They form the basis for many modern applications, for example in SAP Fiori or mobile business applications.

Extension scenarios - for example with the SAP Extension Suite - also benefit from OData V4, as extensions can be developed quickly and modularly. The harmonization of data models and interfaces across the entire SAP ecosystem is also simplified by standardization.

OData V4 is integrated into SAP Fiori apps via the SAPUI5 framework. The apps use a so-called OData V4 model, which automatically sends requests to the connected service - for example to load data or save changes. Data is transferred in the background (asynchronously) in compact JSON format.

The “manifest.json” file defines how the apps are connected to the OData service: Among other things, the data model, available data sources (entity sets) and filter options are defined there.

User actions - such as approving an order - can be linked directly to so-called actions in the service via buttons or menus. In this way, the interface reacts immediately to user input and accesses the stored business processes in a targeted manner.

Another plus: SAPUI5 recognizes many of the OData statements automatically. This significantly reduces the development effort, as many UI elements configure themselves based on the metadata. This results in a high degree of consistency and user-friendliness in the resulting apps.

SAP OData V4 services are subject to strict security standards. Depending on the configuration, authentication is carried out using the following methods:

• OAuth 2.0: modern, token-based authentication procedure (particularly widespread in cloud scenarios)
• SAML (Security Assertion Markup Language): standardized procedure for single sign-on (SSO) authentication
• Basic Auth: simplest form of authentication with user name and password

Access to services is role-based, with authorization objects stored in the SAP system. HTTPS can also be activated for encrypted transmission.

Auditable logging of all requests and actions is possible. This ensures that all business-relevant processes are traceable and compliant. The security of the services is regularly updated via security patches.