Steps:

1. Create a Date Table by entering the the following DAX formula Dates = CALENDARAUTO()
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2. Change the new column Dates -> Date to have the Data Type of Date
3. Change the Dates -> Date column to have the format of your choince (e.g. "m/d/yyy")
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4. Create a relationship between the Dates -> Date column and the Sales -> DateKey column
5. Hide the column named Sales -> DateKey
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