Basics of Mass Data Transfer
Before you begin the initial data load from a non-SAP system to an SAP system, you have to answer the following questions:
You have to determine which business object type can be allocated the imported data in the destination system. This is important because the business dependencies are mapped across an object model in the R/3 System. For example, if you want to transfer data involving sales processing, then business objects Material, Customer, and Sales document are involved.
You have to determine the data transfer technique to use for each involved business object type. The techniques BAPI, batch input, and direct input are available for loading the data into the target system. For details of the individual techniques, please refer to the description of phase Transferring the Data into the R/3 System.
The key feature of the data transfer is that data can only be transferred from a non-SAP system to an R/3 System when it is available in SAP format. For this reason, the data from the non-SAP system initially has to be extracted into a file, and then copied into a transfer file in SAP format. In turn, this transfer file is the foundation for the actual data import into the R/3 System.
The entire data transfer usually takes place in five technical phases, which are illustrated in the following diagram.
These phases are described in detail below:
This phase involves answering three related questions:
This step is required to assign the transferred data to the correct SAP structures later.
A power company manages its customers for electricity, gas, and water in three separate systems. These three systems are to be merged in a single R/3 System. If customers exist who purchase both gas and water from this company, for example, then the data on these customers may have a different status in the different systems. For this reason, the customer data from the individual systems first has to be cleaned up and unified before it can be transferred to the R/3 System.
In this step, the determined data is extracted from the non-SAP system to a file. The data in this file still has the format of the non-SAP system. The following options are available for extracting the data:
Data from a non-SAP system can only be transferred to an R/3 System when it is available in SAP format. For this reason, the file containing the data in the non-SAP system format has to be transformed into a transfer file in SAP format.
Because the format of the data extracted from the non-SAP system usually differs from the SAP format of the transfer file, mapping between the different structures is required. To perform this mapping, you will have to analyze both the fields and structures of the data to transfer and the involved SAP structures, in order to determine how the conversion should be performed.
The following options are available for performing the actual mapping:
Before you can import the data from the transfer file to the R/3 System, you have to answer the following questions:
This question must be answered because dependencies may exist between business object types that require the data to be transferred in a specific order.
The following three standard techniques are available for the data transfer:
Calling a BAPI in the appropriate application transfers the data to the R/3 System. If BAPIs are used as interfaces to the SAP system, the same technique is used as for the continuous data transfer between R/3 Systems or between non-SAP systems and R/3 Systems via ALE.
For more information on data transfer using BAPIs, please see Process Flow of the Mass Data Transfer using BAPIs.
Batch input is a standard technique used to transfer large volumes of data into the R/3 System. In the process, the transaction flow is simulated, and the data is transferred as if it were entered online. The advantage of this procedure is that all the transaction checks are performed, which guarantees data consistency.
For detailed information on batch input, please refer to the Basis documentation on batch input sessions under Data Transfer: An Overview of Batch Input Folders.
During direct input, the data in the data transfer file is first subjected to various checks, and is then imported directly into the R/3 System. The R/3 database is updated directly with the transferred data.
Important:You should use BAPIs exclusively to transfer data in Release 4.6A and later.
After the data has been transported into the R/3-System, it must be checked for completeness. It must be ensured, for example, that the sum of the data transferred into the R/3 system is the same as the sum of data from the external system.
SAP created the DX Workbench for Release 3.1 and later to support the transfer of mass data. Starting in Release 4.6A, this tool provides integrated project management for all the steps involved in transferring data to the R/3 System.
In particular, the Data Transfer Workbench offers the following functions:
For more information, please refer to the documentation for the DX Workbench underData Transfer Workbench.