From Power BI Connector version 1.3.0, the possibility to export expanded Reference fields was added. It is possible to get not only the direct parent-field, but go deeply into tables dependencies and select the child-fields, that you need.
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Child-fields can also be a Reference type(highlighted by green color) and contain their child -fields. Which table is used as a reference can be checked on the backend side.
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New child-fields can be found as additional columns in a selected table. Data will be shown according to Display settings for each table.
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NOTE: Dependent on user permissions for tables, there are different lists of fields that will be able to select on the data source page.
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