Add a column with NULL values in Tableau Prep

Question

I am using Tableau Prep to load PDFs to SQL server. The PDF contains several tables. All the columns except the one with NULL values is not created. If there are 12 columns in the PDF, I'm seeing only 11 in the Output. There's a column that has NULL values. Is there a way to create a column to have NULL values? The column is blank initially(eg, Jan, and values are being populated from Feb onwards) and then is being populated with float values. The PDF's need to be loaded daily. I created the column but it gives an error 'Error adding Text[columnname]. Expected different text.' Prep Version is 20.3.3. Do I continue loading the Jan files and then is it possible to add the column and map it Feb onwards? Is there another way to accomplish this? Thank you in advance.

Answer 1

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