The function "Matrix of Usage: InfoProvider Objects in Queries" can be found in Where-Used Analysis and in the search view:
This function can help you get information about the usage of InfoObjects, Reusable Key Figures, Structures, or Variables of a specific InfoProvider. It identifies all Queries based on the InfoProvider. After that, it searches for usages of the InfoObjects, Reusable Key Figures, Structures, and Variables in Variables in these Queries.
You can get an idea about which InfoObjects, Reusable Key Figures, Structures, or Variables are Variables are defined on an InfoProvider, but not used in Queries.
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