Report builder: (Null) values in query designer when [] brackets in column name

Hi, SCWO 

The problem you are experiencing is that when connecting to the Power BI semantic model, the column names contain square brackets ( [ ]), causing (NULL) values to appear in Report Builder, which may be due to the way the Query Designer handles special characters in column names. Here are a few ways to resolve this issue:

Adding Aliases to Columns in a DAX Query
You can add aliases to columns in a DAX query to avoid the use of square brackets. The following is an example of how to add an alias to a column:

EVALUATE 
SUMMARIZECOLUMNS(
    'fctEnergy'[Datum], 
    'fctEnergy'[Abriss [0/1]] AS Abriss,
    'fctEnergy'[Einspeisung Gasturbine] AS Einspeisung_Gasturbine,
    'fctEnergy'[Einspeisung K 07 [kW]] AS Einspeisung_K07_kW
)

If possible, you can rename the columns in Power BI Desktop to remove the square brackets and then publish the updated model. This method ensures that all downstream users and tools that reference these columns do not encounter issues.

In Report Builder, you can create datasets with custom queries and rename columns within them. Here is how to define a query directly in Report Builder:
In Report Builder, go to Dataset Properties.
Select Query Designer and switch to Edit as Text mode.
Write a custom DAX query with aliased column names, similar to the following:

EVALUATE 
SUMMARIZECOLUMNS(
    'fctEnergy'[Datum], 
    'fctEnergy'[Abriss [0/1]] AS Abriss,
    'fctEnergy'[Einspeisung Gasturbine] AS Einspeisung_Gasturbine,
    'fctEnergy'[Einspeisung K 07 [kW]] AS Einspeisung_K07_kW
)

hackcrr

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