Show TOC

Multiple Origin Composition Locate this document in the navigation structure

 

Multiple origin composition (MOC) is the ability to collect data from different backend systems, aggregate them in one single service and updating different backend systems while using the same user. Thus a service can be made available for several system aliases. For example, you could have two identical systems, one located in America and one in Europe, and combine them. MOC is also used for CREATE calls and the metadata. At present, CREATE calls cannot be done in all configured backend systems, but only in the default system.

Note Note

  • This feature is only supported in Standard Mode.

  • This feature is relevant only for entity sets with an annotation of addressable=true.

  • Implementing this feature creates a different version of the service (The SAP__Origin field is added).

End of the note.

Proceed as follows to use the MOC:

  1. Customize your service to support MOC.

    1. From the SAP NetWeaver Gateway system, activate the desired service. For information on how to activate your service, see Register your Service in the SAP NetWeaver Gateway System.

    2. Open transaction SPRO and choose SAP Reference IMG.

    3. Navigate to   SAP NetWeaver   Gateway   OData Channel   Administration   General Settings   Activate and Maintain Services   to add the system aliases for the relevant backend systems and define the desired default system.

      1. In the Service Catalog list, select the desired service. The service appears in the ICF Nodes section on the lower left corner of the screen.

      2. In the ICF Nodes section, select the Standard Mode ICF Node.

      3. In the System Aliases section, choose System Alias to add the system alias.

      4. Choose New Entries or select an existing entry and choose Copy.

      5. In the Service Doc. Identifier field, enter the ID of the service document followed by an underscore and the 4–digit version number (for example, _0001).

      6. In the SAP System Alias field, enter the relevant system alias. Only one system is to be defined as the default.

      7. Repeat as necessary to add the desired backend systems.

      Note Note

      The default system is used whenever the service is not called as MOC. If you have defined more than one default system alias, the first system is used as the default.

      End of the note.

  2. Test the service.

    1. On the SAP NetWeaver Gateway system, open the SAP Reference IMG in transaction SPRO and navigate to   SAP NetWeaver   Gateway   OData Channel   Administration   General Settings   Activate and Maintain Services  .

    2. Search for the desired service with the Filter icon.

    3. Select the desired service and choose Call Browser under ICF Nodes.

      An example URL for RMTSAMPLEFLIGHT looks as follows: http://<host name>:<port>/sap/opu/odata/iwfnd/RMTSAMPLEFLIGHT;mo/

    4. Make sure that the SAP__Origin field appears in the service's metadata.

Parallelization of Multiple Origin Composition

When using multiple origin composition you can determine both the minimum number of backend systems and the maximum number of parallel backend calls. For this a new IMG activity has been added: On the SAP NetWeaver Gateway system, open the SAP Reference IMG in transaction SPRO and navigate to   SAP NetWeaver   Gateway   OData Channel   Administration   General Settings   Define Parallelization for Multiple Origin Composition  .

You can use this parallelization of READ_ENTITYSET to several backend systems to achieve optimized performance. In the In the IMG activity you can set the following configuration parameters:

  • Minimum Number of Backend Systems can have following values:

    • 0: No parallelization

    • n: Parallelization will only be done from n backend systems onwards

  • The maximum number of parallel backend calls is always based on current resources of the SAP NetWeaver Gateway hub system. Additionally, you can use parameter Maximum Number of Parallel Backend Calls to limit the use of current system resources. The default value zero (0) means it only depends on current system resources.

Performance Improvement

In case of serialization the duration of a READ_ENTITYSET within a hub system is the sum of all backend calls. Contrary to this, the duration in parallel mode is just the maximum duration of all backend calls and means a minimal overhead for parallelization.

Parallelization and Skiptoken

If server paging is realized in any backend data providers, then the OData consumer will only receive results up to this backend including a skiptoken. The next call with this skiptoken or any other call with skiptoken will not be parallelized because the result has to be continued by the backend system which returned this skiptoken before.

Changesets

In the context of multiple origin composition, changesets are also supported. All changeset operations for one backend are collected and sent to this backend via one RFC. You can find an example in SAP Note 1890049.

More Information

Error Log