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When looking at a report created from a dataset, there is not a method to identfiy identify the source of field data.
Step 1: Identify the dataset the report uses.
Step 2: Download a local copy of the dataset from app.powerbi.com
Step 3: Edit the query that generates the table in question in the downloaded local copy.
Step 4: Read through the rename step in the query on the right hand side by viewing the native query.
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