SAP Datasphere, SAP BW bridge: Demystifying the Remote Conversion

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Abstract

This blog intends to provide an overview about the end-to-end process of the Remote Conversion to SAP Datasphere, BW bridge. For a deep dive into the details of all activities involved, check our SAP Datasphere, SAP BW bridge Runbook which contains practical examples, tips and recommendations based on experience with real customer projects.

 

Overview

The Remote Conversion offers the possibility to transfer the metadata plus the business data from your on-premise BW system to a target BW system (also called receiver system), which can be a BW/4HANA or a BW SAP BW bridge system. The Remote Conversion to BW/4HANA is available since 2017 and now is also available for Datasphere, BW bridge.

The transfer of only the metadata is offered by the Shell Conversion. The metadata transfer is also part of the Remote Conversion process therefore we can say that the Shell Conversion of a subset of the Remote Conversion. Which option to use depends on some variables such as the scope definition, number of objects and data volume involved.

BW bridge is a feature of Datasphere and offers the possibility to use BW artifacts in SAP Datasphere. The ABAP Tenant (where the BW modeling happens) is integrated by its own space into SAP Datasphere The tables of the ABAP Tenant (e.g. ADSOs, InfoObjects) can be exposed as remote tables in the BW bridge Space of Datasphere and shared to be consumed by other spaces.

The BW bridge space has limitations and its main functionality is to expose the shared remote tables to other spaces. Data Flows, views, etc. using the remote tables can only be created in other spaces based on the shared remote tables.

 

Figure 1: Remote Conversion overview

 

There are some differences between the Shell and Remote Conversion in terms of the scope collection logic for the metadata transfer, especially because of the relationship and dependencies of the request management. When using the Remote Conversion, data and request Information need to be copied and converted from the sender into the receiver system (Request ID to TSN), therefore all objects on which a data request is touching become relevant for the scope collection in order to ensure consistency.

The metadata transfer converts object types (TLOGO). For example, Classical DSOs and InfoCubes to Advanced DSOs; PSAs to Advanced DSOs (depending on the data flow, it can be optional or mandatory); InfoPackages to DTPs.

 

Figure 2: Metadata transfer

 

Prerequisites

The Remote Conversion to SAP Datasphere, BW bridge is supported by the tooling from BW 7.3 (SP10 and higher) and BW/4HANA 2021 (SP00 and higher) releases. The DMIS add-on installation is required (not needed for the Shell Conversion).

For detailed information about pre-requisites and preparations, see: SAP Note 3141688 - Conversion from SAP BW or SAP BW/4HANA to SAP Datasphere, SAP BW Bridge.

This note contains a .zip file (SAP_Bridge_Transfer_Note_Analyzer_YYYY-MM-DD.zip) with .xml files for each scenario. There are 2 (two) for the Remote Conversion: 1 (one) for when the sender system is on BW 7.x and 1 (one) for when the sender system is on BW/4HANA.

Figure 3: Note Analyzer .zip file

 

You should import one of these 2 files (depending on your sender system release) to the sender system by using the Note Analyzer report (it is also included into the above .zip file).

The file Source_System_for_SAP_BW4HANA_YYYY-MM-DD.xml is also required to be imported to the source systems which are connected to the sender system (e.g. ECC, SCM, etc.). This is required especially for ODP enablement of the DataSources (see SAP Notes 2481315 and 2232584)

The imported .xml files contain a list of notes which are required to be implemented to enable the Remote Conversion. It brings enhancements and corrections in a frequent manner therefore it is important and recommended to always have the latest version implemented.

Differently when the receiver system is on BW/4HANA on-premise, there is no .xml file to be imported to the receiver system as BW bridge is on cloud.

Differently when the receiver system is on BW/4HANA, backend access to BW bridge via SAP GUI is not possible for partners and customers. BW bridge objects and data flows are only accessible via Eclipse/HANA Studio (BWMT).

 

Data Transfer Logic

For the business data transfer, programs are automatically generated for each table in scope, to select, transfer and insert the respective data into the receiver system. Cluster tables are used to control and manage the data transfer process.

Figure 4: Remote Conversion logic

 

One (1) program is generated for each phase/step of a table processing:

1. Read (data selection).


2. Move (transfer of the data from the sender system to the receiver system).


3. Convert (insertion of the data into the corresponding tables in the receiver system).

 

Delta Queues Cloning

Besides the business data transfer automation, another important capability of the Remote Conversion is the delta queue cloning. Delta queues are cloned and synchronized before the data transfer, which is beneficial because it ensures consistency of the delta loads after the data transfer is finished. For example, a delta DataSource that already loads data into the sender system will be cloned and start to extract deltas also to the receiver system.

No downtime is required (data load freeze is recommended to speed up the cloning and synchronization). This capability allows a smoother transition to BW bridge or BW/4HANA through the co-existence of both sender and receiver systems to get data loads from that DataSource. This can be beneficial if you do not want to immediately shutdown/decommission your actual productive sender system (e.g. if you wish to extend the validation period with business users and analysts or implement a hybrid scenario). The Shell Conversion does not offer this capability and in that case all delta DataSources in scope should be manually initialized/loaded to the receiver system after the metadata transfer.

Figure 5: Delta queue cloning

 

Conversion Cockpit

The Conversion Cockpit contains the sequence of all activities considering the end-to-end transfer process. It can be accessed via the transaction CNV_MBT_PCT.

Figure 6: Conversion Cockpit and Task List

 

The Conversion Cockpit is the main control interface and central point of access of the Remote Conversion end-to-end execution. Differently from the Shell Conversion, which process is fully controlled by the Task List (transaction STC02). The integration of the Task List with the Conversion Cockpit ensures that there is a direct link between the metadata collection/transfer and the data collection/ transfer in a subsequent activity.

 

Sequence of Activities (Phases)

There are 3 types of views to perform the transfer execution – Standard, Extended and Expert.

Figure 7: Conversion Cockpit – Phases

 

The activity groups (also called phases) are:

1. Package Settings (Active Phase): starting point where the transfer package is created and the RFC settings maintained.


2. Collect Scope and MetaData Transfer: definition of the objects that will be part of the scope and transfer of the respective objects (metadata).


3. Setup Phase: preparations for the data transfer, table pool and mappings creation, DDIC comparison.


4. Generation Phase: creation of the programs that will enable the data transfer and optimization capabilities (parallel read).


5. Preprocessing Programs During System Lock: PSA extraction, copy and sync of delta queues, data changes are locked.


6. Migration Phase: processing of the tasks related to the data transfer (selection, transfer and insertion).


7. Post Processing Activities During System Lock: validations, RSRV checks and repairs, hierarchies and number ranges rebuild.


8. System Settings After Migration: truncate temporary tables (clusters and shadow InfoCubes), package completeness.

 

Datasphere Integration

When using the Remote Conversion for moving to SAP Datasphere, BW bridge, the BW objects and corresponding business data which already exist in the BW sender system are transferred to BW bridge and imported as remote tables to Datasphere (into the BW bridge space).

Figure 8: Datasphere, BW bridge integration

 

As a feature of Datasphere, BW bridge enables the integration between the ABAP and cloud “worlds”, by creating new objects directly in the BW bridge system or transferring them from on-premise BW or BW/4HANA systems.

For the tables which were in the scope and had their corresponding data transferred to BW bridge through the Remote Conversion, they can now be imported as remote tables via the SAP Datasphere Data Builder.

Figure 9: Datasphere - Import Remote Tables in Data Builder

 

References

The Remote Conversion to BW bridge is a complex process and involves many tasks. For a successful implementation, it is important to follow the prerequisites and sequences as well as to invest time on the preparations for the project.

Besides the SAP Datasphere, SAP BW bridge Runbook, there are some important documents which may serve as a reference for the planning and execution of your Remote Conversion to BW bridge:

Document	Available at	Comment
Getting Started with SAP Datasphere, SAP BW Bridge	Getting Started with BW bridge	Get onboarded to SAP Datasphere, SAP BW bridge and prepare your environment for acquiring data via the bridge
Using SAP Datasphere, SAP BW Bridge in SAP Datasphere	Using BW bridge	Import SAP BW objects from SAP Datasphere, SAP BW bridge as remote tables into SAP Datasphere
Information/ Restrictions Note for SAP Datasphere, SAP BW bridge	SAP Note 3117800	Provides information about restrictions in SAP Datasphere, SAP BW bridge
Conversion from SAP BW or SAP BW/4HANA to SAP Datasphere, SAP BW Bridge.	SAP Note 3141688	This SAP Note describes the different paths to get from SAP BW or SAP BW/4HANA to SAP Datasphere, SAP BW bridge.
Simplification List for SAP Datasphere, SAP BW bridge	SAP Note 3154420	Provides collection of all relevant SAP Notes related to Simplification List for SAP Datasphere, SAP BW Bridge
Data Warehouse Cloud, First Guidance: Development Guidelines and Naming Conventions	First Guidance	This document serves as a guideline for creating (reusable) data models for various source system connections, based on best practices and experience from existing projects about development as well as naming conventions.

 

In case of questions about the Remote Conversion to BW bridge, feel free to contact me.

Many thanks to my colleagues Klaus Peter Sauer, Udo Baetz, Eduard Schoonbrood, Claudia Fiess, Thomas Rinneberg, Dominik Graus and Konstantinos Stergios for your reviews.