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morganhouse's avatar
morganhouse
New Member
4 years ago

Multiple tables vs single table

Hi all,
I am a new user. I wanted to know what the purpose is for importing/creating multiple tables and then establishing relationships instead of importing one table that includes all of your data? Are there any videos that explain why this is important or is there anyone here who wouldn't mind taking a few min to explain it to me?
Thanks so much!
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2 Replies

  • themistoklis's avatar
    themistoklis
    Community Champion
    4 years ago

    Hello morganhouse ,

     

    When you add multiple tables to PowerBI and you specify the cardinality then this means that you are creating a data model.

     

    For experienced data engineers this is similar to creating a relational database model.

     

    I think you should look for normalized and denormalized data model.

    It explains the benefits and drawbacks for having a data model vs one table

    https://medium.com/analytics-vidhya/database-normalization-vs-denormalization-a42d211dd891

     

    Also, It always depends on the size of data that you will import to PowerBI

    • morganhouse's avatar
      morganhouse
      New Member
      4 years ago

      Thank you, themistoklis .

      I do understand the concept behind it. However, I have having trouble actually implementing it and wondering if and when I should. 

       

      I provided a (denormalized) table that I am working with. Would there be a beenfit to separating this table out into different tables? Obviously there are a lot of redundancies (Cost center, year, month, week ending date, etc...). 

       

      The next question is, if I did separate them out, would the main data set still need to be part of the PowerBI file?

       

      I know this is a very low-level question and I do truly appreciate your willingness to take a look and to help.

       

      Thank you again.

       

      Payroll Data Abbreviated