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Regular Visitor

Union Function for multiple columns

Hi guys, I have a bunch of columns that contain email address, so I'm trying to make these columns a dynamic value for the email recipients' reference. The problem is all the columns have a duplicate value of email address, I have tried to compose with union function, there is no single error when I run the flow but the duplicate value is still there. So I tried to select only one column and use the union function and it works. But when I select more than one column, the duplicate value is still there, does anyone know where I get wrong?



this is just an example, actually, I have 28 columns of emailsrwt7zjjhkln71.png

Super User
Super User


I may not be 100% clear on what you are trying to do, but try this:

  1. Create an array variable
  2. Append each of the email address to the array (append to array variable)
  3. Use the union() expression and provide the array variable for both parameters
    1. The result should be a list of unique email addresses.


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Regular Visitor

Hi @ScottShearer thank you so much for your response, but it gave me an error message "... of type 'Array' cannot be appended to the variable 'Email' of type 'Array'. The action type 'AppendToArrayVariable' only supports values of types 'Float, Integer, String, Boolean, Object". 


would you mind telling me where did I get wrong?



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