Data Structure and Data Types of an R/3 System

The R/3 System consists of various data types.
Certain types of data are only accessible from a particular client. Such data types include business application data (documents, material master records, and so on) as well as most Customizing settings.
These settings:
Define the customer's organizational structures (distribution channels, company codes, and so on)
Adjust the parameters of R/3 transactions to fit customer-specific business operations
Client-specific data types are closely interdependent. Thus, when application data is entered, the system checks whether the data matches the client's Customizing settings. If there are inconsistencies, the application data is rejected. Therefore, application data usually only makes business sense in its specific Customizing environment.
In addition to client-specific data, R/3 can have other settings that, once defined, are valid for all clients.
This data includes:
Cross-client Customizing, such as printer settings
The R/3 Repository, which contains all objects in the R/3 Dictionary (tables, data elements, and domains), as well as all ABAP programs, menus, CUAs, and so on
In the case of cross-client settings, an ABAP report that was originally developed in a certain client may be immediately usable in another client.


Corresponding to the various data types in the R/3 System, there are various types of changes and adjustments to data.
The R/3 System is delivered in standard form and must be adjusted to the customer's requirements during the implementation phase. This procedure is called Customizing. As shown in the graphic,Customizing includes both client-specific and cross-client Customizing data. An R/3 upgrade may require a limited amount of additional Customizing.
Unlike Customizing, enhancements or adjustments to the R/3 Repository are not required to operate an R/3 System.
To adapt the R/3 Repository to a customer's requirements, the customer can develop in-house software.
In addition, customer enhancements can be added to the R/3 Repository. In this case, customer defined objects are used to complement the SAP delivery standard. The precise locations where enhancements can be inserted are specified by SAP.
Finally, R/3 objects such as reports and table definitions can be modified directly. In this case, the R/3 Repository delivered by SAP is not merely enhanced; it is changed. During the next R/3 upgrade,these modifications may therefore need to be adjusted before being incorporated into the new Repository. The adjustment can be a time-consuming process.


Customizing settings must be transported between clients.
Changes to the R/3 Repository must be transported between R/3 Systems.