In the IDE you just add the .dat files to the respective run configuration.
For the command line tool oplrun you either add the .dat files to the command line or (when running a project) to the run configurations in the project's XML file.
By the way, did your user look at
IDE and OPL > CPLEX Studio IDE > Getting Started with the IDE > Getting Started Tutorial in the manual? In particular the "Populating and Executing the run configuration" section? This contains a detailed explanation of how to do this in the IDE.
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Daniel Junglas
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