Questions on converting an 'Import Mode' query to 'Direct Query'

Hi D_PBI 

Whether all applied steps in Import mode can still work in DirectQuery mode depends on whether this query can achieve query folding. For a DirectQuery storage mode table, the Power Query query must achieve query folding. If the query cannot achieve query folding in DirectQuery mode, it will require you to convert this query to Import mode. 

For relational DB data sources, you can right-click the last applied step in the Query Settings pane. If the View Native Query option is enabled (not greyed out), then the entire query can be folded. You could refer to this document to see which transformations can achieve or prevent query folding.

For the second question, you can switch to Model view in Power BI Desktop, select a table and expand Advanced tab in the Properties pane to see which mode the table is. 

Other references for query folding:

Query folding basics | Microsoft Docs

Query folding guidance in Power BI Desktop - Power BI | Microsoft Docs

Regards,
Community Support Team _ Jing
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