Missing Value node column setting variables

Hi Experts,

I have several columns which would use different method for missing values.

Such as columnA uses Fix Value, columnB Do Nothing, columnC use *Previous Value…

I know this can be done for static setting each column separately in Column Settings.

However, I try to use a dynamic way to adjust corresponding column in my config table and specify different method for each column.

I found I can get a new column 0 in Flow Variables once I add a column to deal with missing value in Column Settings tab.

Since I can pass the column name variable into colNames, but I cannot figure out what does the variable “FactoryID” mean?

Maybe there is a list to show the method for missing value handling?

BR,

Wade