Bug or normal? Value following casing of first instance of the same value

[olimilo]

This came up today, I have a query with the following test data:

ID	Name
1	TEST
2	Test
3	Test
4	test
5	TEST

When loaded to a table visual, it looks like this:

I tried it with another test table where the first value is "test" and "tEst" instead of "TEST" and the output is the same:

Is this a bug or is this normal behavior? No summarization or other steps were run in the queries to create the tables.

[TomasAndersson · Accepted solution]

Hi!
It's not a bug. DAX is case-insensitive and treats strings with the same characters, not matter their case, as equal. 

So if TEST is the first string in a column with, T, E, S, T, all following strings will also be TEST no matter if they're loaded as TeST, test, tesT or something else.

You can read more about it here: Letter case-sensitivity in DAX, Power BI and Analysis Services - SQLBI  

[olimilo]

Thanks @TomasAndersson @Greg_Deckler 

I thought I would be able to fix this by pulling the case-sensitive data from a different table but it looks like the behavior is still the same.

Is there any other way to approach this? We are getting the data from dataflows so we are unable to set case-sensitive collation.

[Greg_Deckler]

@olimilo @TomasAndersson This is not 100% a DAX thing, the SSAS Tabular data model is case insensitive. Here is a blog article on one way of getting around this. Chris Webb's BI Blog: Power BI And Case Sensitivity Chris Webb's BI Blog (crossjoin.co.uk)

[Greg_Deckler]

@olimilo Unfortunately this is normal behavior. The data model in Power BI is set to ignore casing so TEST is the same as Test is the same as test is the same as tEst as far as Power BI and DAX are concerned.