About

• This document is created to provide basic understanding of what is BW/4 HANA, how is it different from SAP BW.
• This document covers a case study what changes will be required in customers’ BW Global system where ECC, web-services and flat-file data sources are involved
• What are the important notes to be applied for beginning further technical analysis and to proceed with migration preparation phase

What is BW/4HANA

• SAP’s New Data warehouse
  • SAP BW/4HANA is SAP’s next generation data warehouse solution
  • It is a new product and not a successor of any SAP BW
• Continuing BW functionalities
  • The core functionality of SAP BW is preserved and the transition to SAP BW/4HANA
  • Can be compared with the transition of SAP Business Suite to SAP S/4HANA
• Reduce Data redundancy
  • BW/4HANA provides a simple set of objects; suited for modelling an agile and flexible layered architecture of a modern data warehouse
• Reduced Number of Objects
  • SAP BW/4HANA drastically reduces the number of data objects hence less maintenance and storage
• Future Roadmap
  • All future innovations will take place in SAP BW/4HANA

SAP BW/4HANA vs SAP BW

SAP BW/4HANA only uses state of the art object types, processes, and object types designed for use on a SAP HANA database.

Converting from SAP BW, powered by SAP HANA brings the following functional changes:

• The SAP Business Explorer tools (SAP BEx tools) are not supported any more.
  • BEx Analyzer will not be available anymore
  • Queries are now defined in SAP BW/4HANA in the BW Modeling Tools
• Different SAP tools can be used for reporting (additional licensing to be checked)
• Modeling in the Data Warehousing Workbench (SAPGUI) is replaced by modeling in the BW Modeling Tools in Eclipse
• Certain object types are not supported any more
  • These are replaced by objects types that are especially primed for use on the SAP HANA database (ex. PSAs are not available anymore)

Paths to SAP BW/4 HANA

• New implementation or fresh start
  • New implementations are the best choice for customers converting from a legacy system or building a system from scratch with new data model only
• Landscape transformation
  • Landscape transformation is for customers who want to consolidate and optimize their complex SAP BW landscape (multiple production systems) into a single SAP BW/4HANA system or who want to carve-out selected data models or flows into a global SAP BW/4HANA system
• System conversion (Relevant to Customer)
  • A system conversion addresses customers who want to change their current SAP BW system into a SAP BW/4HANA system. Using the Transfer Toolbox provided by SAP, the SID of the system can be kept (in-place conversion) or a new SID can be used (remote conversion or shell conversion)

SAP BW/4HANA System Conversion

•      In-Place Conversion

• Full system conversion of an existing SAP BW installation (keep same SID)
• Step-by-step in-place transfer of classic objects into their HANA-optimized counterparts
• Followed by a system conversion to SAP BW/4HANA
• Minimum start release: SAP BW 7.5 SP 5 powered by SAP HANA

•      Remote Conversion

• Start with SAP BW/4HANA as green field installation (new SID)
• Support of carve-out and consolidation scenarios
• Transport data models and remote data transfer (including Unicode conversion)
• Risk mitigation due to parallel system
• Minimum start release: SAP BW 7.0 or higher on Any DB

•      Shell Conversion

• Similar to Remote Conversion but without data transfer
• Accelerate greenfield approach by transferring and converting data models and flows
• Minimum start release: SAP BW 7.0 or higher on Any DB

In-place Conversion (Basic Sequence)

• Discover / Prepare Phase
  • Check system for BW/4HANA compliance (gather information about objects and code that needs to be transferred or changed), estimate effort for the conversion project
• Explore / Realization Phase
  • Transfer legacy objects into HANA-optimized counterparts, system conversion, post conversion tasks

•      SAP BW/4HANA Transfer Cockpit

• The SAP BW/4HANA Transfer Cockpit is the single point of entry for tools required for transitioning SAP BW systems to SAP BW/4HANA
• Collection and Display Of Statistics Of Transfer Processes
• Tools for Preparation Phase
  • Pre-Check Tool
  • Sizing Report
  • Code Scan Tool
  • Clean-up Reports
  • Standard Authorization Transfer –Initial Run
• Tools for Realization Phase
  • Scope Transfer Tool
  • Standard Authorization Transfer –Delta Run
  • Deletion of Technical Content
  • Switching Operation Mode
• Transfer Cockpit (transaction RSB4HCONV) for In-place Conversion
• System statistics showing number and size of remaining InfoCubes and classic DataStore objects.
  • Top 10 shows, which have most records.
• Prepare Phase includes pre-check tool, sizing report, code scan tool, clean-up reports, and initial run of authorization transfer
• Realization Phase includes scope transfer tool, delta run of authorization transfer, and change of operation mode

•      Pre-check Tool

• Check your SAP BW system using the pre-check tool (program RS_B4HANA_CONVERSION_CONTROL)
  • Check complete system
  • Check individual transport requests
  • Display logs of previous checks

General Findings after analysis

• Navigational Attributes are not generated when DSO/Cube are converted to Advanced DSO
  • These are permitted in Composite Providers for Reporting
  • Individual Transformations where used will require adjustments
• x Objects are not supported any more
• Extraction from PSA is not supported
  • PSA and Infopackages can be skipped or converted to ADSO and DTP
• Only HANA, Flat File source and ODP systems are supported
• Web Service Source System are not supported
• BEx analyzer, Web Templates are not supported
• Info Object Catalogs are not supported and to be converted to Info Area
• Integrated Planning (BW-IP) not supported and to be converted to BPC embedded

Findings on Customer BW System

• BEx reporting:
  • BW Queries will continue to work where BEx analyzer and Web template will not be supported
  • Adoption of Analysis Office is preferred before BW4/HANA migration
• BW-IP
  • BW-IP has to migrate to BPC Embedded
• Source systems
  • ECC source system connections needs to be replaced with Operational Data Provisioning (ODP) Source System
  • Alternate for Web services to be analyzed. Web Service source system not supported (2441826 – BW4SL – Web Service Source Systems)
  • No support for Hierarchy DataSources / Extractors (2480284 – BW4SL – Hierarchy DataSources). Further investigation required Need to find out alternative
  • PSA & info packages are eliminated from BW/4 objects – POC required to confirm flat file data sources are supported through DTP
• Authorization
  • No impact on authorization as such – but all the roles and profiles have to be checked and replace the existing cube names with newly created ADSOs name if applicable

Recommendation (Customer also thinking S/4 HANA migration for ECC system)

• SAP BW/4HANA is completely independent of S/4HANA. BW/4 HANA is not a prerequisite for S/4HANA, and vice versa.
• All the pre-requisite activities can already start as current version of BW 7.5 sps 007 supports it for future readiness.
• In-general SAP’s initial understanding while designing SAP S/4 HANA (2015 earlier) was that BW not required any more but this ended as not true. S/4 HANA is mainly taking out and replacing Operational Reporting from BW but need of Data Warehouse will continue to be in place
• BW4/HANA is designed to support Big Data innovations and any future enhancement will be in BW4/HANA. Hence BW4/HANA migration should be considered
• As S/4HANA provides operational reporting. Scope of BW would revise after S/4HANA migration hence actual BW/4 HANA conversion should be planned after S/4. Preparation can / should be started ahead and in parallel.

Technical Next Steps

• Reduce the data volumes as much as possible on current system for shorter conversion duration (Regular Housekeeping)
  • Housekeeping to reduce overall system space by deleting system logs
  • Simplify Process chain – indexes, rollup, dbstate, Aggregates
  • Delete unused / test queries, cubes, dsos etc..
• Following notes to be reviewed and applied for pre-check analysis
  • SAP Note 2591784 to prepare the SAP BW system for the readiness check
  • SAP Note 2296290 to collect the HANA sizing data (/SDF/HANA_BW_SIZING)
  • SAP Note 2399707 to collect the simplification item relevance information
  • SAP Note 2567324 to collect information about object compatibility
  • SAP Note 2575059 for SAP Readiness Check for SAP BW/4HANA
  • SAP Note 1909597 for latest version of BW HANA Migration Cockpit ZBW_HANA_MIGRATION_COCKPIT
  • SAP Note 2577045 for ABAP Code Scan
  • SAP Note 2383530 Conversion from SAP BW to SAP BW/4HANA
    • Important t-code RSB4HCONV & program RS_B4HANA_CONVERSION_CONTROL
  • POC should be done to understand complete impact on system

Reference

• https://www.sap.com/
• https://blogs.saphana.com/tag/bw4hana/