RELATED, MERGE table or none

If you can do it, 2 should provide the fastest calculations because you would want to do that in the Query Editor so there is less work to be done calculating things during display. All 3 will work however.

Sample data though would be very helpful to provide specifics. Please see this post regarding How to Get Your Question Answered Quickly: https://community.powerbi.com/t5/Community-Blog/How-to-Get-Your-Question-Answered-Quickly/ba-p/38490

Anonymous,

Just pick columns between mutiple tables may cause some issue or mistabke. So to be general, I would suggest you to merge tables, not use DAX function like RELATED() or RELATEDTABLE() in report level because the DAX engine is much slow than power query engine. All in all, a much more simple and fastest way of data transformation is to do this in database using SQL.

Community Support Team _ Jimmy Tao

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