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Anonymous's avatar
Anonymous
Not applicable
7 years ago
Solved

Which one best approach loading data

Hi Team,

 

I am confussion when get data

which one is best

1.calculated columns  and load one table( i am created one table),importing data in Power BI

2.i have one table then select statement i am also calculated column query importing in Power BI

3.after import my column i am creating calculating column

 

which is best method

 

thanks

Shanvitha

Need Help
  • TomMartens's avatar
    TomMartens
    7 years ago

    Hey,

     

    I'm not 100% sure if I understand your question correctly.

     

    Basically there are three options

     

    1. Create all the necessary column in the source system, eg. using a view in SQL Server
    2. Create additional columns in Power Query
    3. Create additional column using DAX creating calculated columns.

    Basically it depends whats better, from my point of view I would prefer 1, but sometimes calculations are more complex and can be executed faster in M or DAX.

    The memory footprint of a calculated column created using M is considered smaller than the column created using DAX, but this is just a fraction, that I always neglect. As I'm more proficient using DAX, I'm using DAX to create calculated columns, I never noticed a performance difference between both types of columns the ones that I created using Power Query or DAX.

    I always avoid to spread the column creation across all 3 possibilities, this is due to the spread of complexity. I always tend to look for my mistakes at one place-

    For this reason, a personal one, it's 1 or 3-

     

    Hopefully this provides some insight to your thinking.

     

    Regards,

    Tom  

1 Reply

  • TomMartens's avatar
    TomMartens
    Super User
    7 years ago

    Hey,

     

    I'm not 100% sure if I understand your question correctly.

     

    Basically there are three options

     

    1. Create all the necessary column in the source system, eg. using a view in SQL Server
    2. Create additional columns in Power Query
    3. Create additional column using DAX creating calculated columns.

    Basically it depends whats better, from my point of view I would prefer 1, but sometimes calculations are more complex and can be executed faster in M or DAX.

    The memory footprint of a calculated column created using M is considered smaller than the column created using DAX, but this is just a fraction, that I always neglect. As I'm more proficient using DAX, I'm using DAX to create calculated columns, I never noticed a performance difference between both types of columns the ones that I created using Power Query or DAX.

    I always avoid to spread the column creation across all 3 possibilities, this is due to the spread of complexity. I always tend to look for my mistakes at one place-

    For this reason, a personal one, it's 1 or 3-

     

    Hopefully this provides some insight to your thinking.

     

    Regards,

    Tom