Maintain Source System Mappings
The "Maintain Source System Mappings" can be found in the tab "Administration" in the ribbon "Maintain SAP Systems".
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Here you can specify which source system is connected to which target system by entering the connection ID.
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The Source System Mapping is important for the correct behavior of some functions of the Performer Suite (e.g. Data Flow or Where-Used Analysis of BW & HANA entities in SAC Entities).