If you want to determine the location of the log files you want to read into your data source with the help of a variable, I’d advise you to create a [Delimited Data Source](https://community.denodo.com/docs/html/browse/7.0/vdp/administration/creating_data_sources_and_base_views/delimited_file_sources/delimited_file_sources) and use a [Interpolation Variable](https://community.denodo.com/docs/html/browse/7.0/vdp/administration/creating_data_sources_and_base_views/path_types_in_virtual_dataport/path_types_in_virtual_dataport#paths-and-other-values-with-interpolation-variables) as a data route.
Doing this you should be able to pass the filepath and filename of the logs you want to read as a variable in the WHERE clause of the query. Thus, you can read out the log files from different locations as desired.
Another possibility would be to check out the [FileSystem Custom Wrapper](https://support.denodo.com/resources/denodo-connect/download/1736) on our support site in case you have access.
Hope this helps!