TM1 Forum

What is the maximum number of columns in a data file that the TI can process?
I did a test and was able to preview a 348 column file in the Data Source tab.

I had a problem at around 140 columns where it started wrapping the variable names into the preview for variable 1,2,3 etc.
I don't think that I ever had an issue importing, just the preview and it seemed to be something to do with the cumulative length of the variable names more than anything else. Not sure that relying on the preview will actually give you any kind of clarity.

Unfortunately I know this does not help you particularly but you may need to test to see where you get unexpected results, unless someone else responds who has already spent the time. I eventually split my file purely because of timing on the source side.

I don't think it is the number of columns as such is a problem but more the total number of characters per line. If I recall correctly the cut off is somewhere just above 4000 chars.