Difference problem

[Betissa]

I am very new in this world of power BI,
Here is my problem: I wanted to calculate the difference between two columns on each column in a different table, here is the formula I use    Ecart2 = ifp_vte1[Mt HT] - RealiseN[Mt HT],
And this reminds me of the following error:   It is impossible to determine a unique value for the 'Mt HT' column of the 'ifp_vte1' table. This can occur when a measurement formula refers to a column that contains many values, without specifying aggregation such as min, max, count, or sum to get a single result.

[BetterCallFrank]

Hi @Betissa,

are there any relationships between your tables in the model?

Can you provide a screenshot of the relationship-view and/or some sample data of what the tables look like?

Frank

[Betissa]

No there is no relationship

[v-ljerr-msft · Accepted solution]

Hi @Betissa,

According to your description and the table structure you provided above, I would suggest you to use Merge Query option to merge the "ifp_vte1" table and "RealiseN" table to a single table first, then you should be able to use the formula below to create a calculate column to calculate the difference.

Ecart2 = newMergedTable[Mt HT1] - newMergedTable[Mt HT2]

For more details about how to use Merge Query option in Power BI Desktop, please refer to this article.

Regards

[Baskar]

Cool,

1. Without relate the table how can we create calculation ?

2. If u create calculated measure u should define the Agregation it is must.

My Suggestion :

Create relationship between these two tables  and try.

or

U don't want relationship . u want only Difference ?  then use sum() infront of column