Sum many column values from each row using DAX

Question

Say I have the table

[3 0 2 5 8 1
 2 9 8 3 1 2
 9 8 3 2 3 1] 

All I want is a function to yield the column

[19
 25
 26] 

without having to type out literally every single column name. My actual data matrix is 30 columns long.

Is there a way to do this that I'm missing? Or is DAX just completely incapable of doing this? I've Googled every single possible combination of the words "sum", "row", "-column", "PowerBI", and "DAX" and gotten absolutely nothing useful. Why in the world would SUM and SUMX automatically assume that the user would always in every single instance ONLY want to sum along dimension 1?

Answer 1

This is not easily done in DAX, as far as I know. Your only options are to spell out all the columns, or drop that requirement and follow the instructions in my earlier answer on how to do this with the Query Editor (i.e. PowerQuery).

Your "why" questions are possibly just uttering of (quite understandable) frustration, but trying to answer them nonetheless: I think the basic idea of tabular reporting is that you aggregate over rows, not columns, and all nearly operations are centered around those. In PowerBI (and many other reporting tools) you need to (un)pivot your data first to do the type of query you're after, which comes full circle to abovelinked solution.