Requesting help in conditional columns

[Manjari]

Hi All, 

I have a data set like below, I use a formula tool to find col4 = (col1+col2)-col3 

But some times not all the columns are present in data set. for eg. I have just col1 and col2 then the col4 formula throws an error. 

Is there a way in Alteryx to mention only if column (col3) is present use this formula (col1+col2)-col3  else just use col1+col2

Col1	Col2	Col3
1.2	6.7	4.6
4.5	5.4	7.8

[Luke_C]

Hi @Manjari 

When you say not present, is the field missing entirely or are the values null for the field?

[Manjari]

@Luke_C : Thank you for responding. 

The field is missing entirely 

[Luke_C]

Hi @Manjari 

I would have an text input with just the headers to union onto the data, that way if col3 is missing it gets created with all null values. That way you can keep the formula consistent.