The function "System Comparison" can be found in analysis reports and in the search view:
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This function compares the entities of two different systems. Therefore you have to select the system and the entities, which you like to compare with each other. Then, the function can be started via the button "Start comparison".
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If the entities of the two systems are compared with each other, certain cells can be highlighted by using conditional formatting. Differences and similarities between the two systems can be determined quickly.
It is possible to choose in which color different or identical values of certain categories (Tech. name, Type, Version, Description, UID, Last changed date, Last changed by, SID) should be highlighted. Moreover, there are further options in the category "Last change date" to get a better overview of the changes within the systems.
When the settings are confirmed via the button "Ok", they will be executed in the system comparison. 
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If you want to get more information about the entities of two systems, you can mark multiple entities (CTRL+ left click) and use the context menu to start the analysis Analyze and Compare BW Entities to compare the buildup in-detail of multiple entities across two systems:
The result opens in the function Analyze and Compare BW Entities.