Struggling with creating correct data model - help please!

Hi DC2024 ,

You can create a separate dimension table for stores, products and date.

For example:

Fact Table:

Product dimension table:

Store dimension table:

Date dimension table:

DateTable = ADDCOLUMNS(
        CALENDAR(MIN('Fact Table'[Date]),MAX('Fact Table'[Date])),
        "Year",YEAR([Date]),
        "Quarter",ROUNDUP(MONTH([Date])/3,0),
        "Month",MONTH([Date]),
        "Day",DAY([Date])
)

Create relationships between them. This is key to a functional STAR schema. 

pbix file is attached.

If you have any further questions please feel free to contact me.

Best Regards,
Yang
Community Support Team

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If I misunderstand your needs or you still have problems on it, please feel free to let us know. Thanks a lot!