Update column names in Join tool using Alteryx analytical app

[adubey054]

Hi,

I am trying to create an analytical app which will give the users an option to enter the fields they would like to be joined in the join tool. I tried using text box and action tool combination however it does not update the columns, it can only update string fields or values in formula or filter tool. Can you please help me understand if it is even possible to update columns using analytical app fucntionality.

[JoeS · Accepted solution]

The part missing is selecting the bit you want to update in the action tool

Here you can see the part you had selected (in blue) was the tool itself, the part that you want to update is the configuration of the join field.

It should look like:

However, to get there you had to do a couple things...

Which leads me to a best practice point I'll always mention to anyone.

The first thing to do when building any app it so build a working workflow first. 

So I went and added in a file to each input, updated the join tool to join on two fields.

I then went a little further and added a file browse for each input and the action to update them.

I also changed the text box's to drop downs and populated them from the files the users selects, as for me allowing a user to enter free text for a field is asking for trouble.

Added a couple of labels, leaving the final interface looking like:

The app is attached, I went through things very quickly above. Let me know if there is anything not clear.

[adubey054]

Thank you, this worked great for my current scenario. I just have one last question. 

Lets say we have 2 files that we are comparing. There are 3 columns that we need to include in the Join tool. In order to do that I created 3 drop down and action tool for left and right side. The workflow works fine when I select the 3 columns via the app. However, if I have another set of file that I am comparing and it only has 2 key fields for the join tool the app won't let me proceed as I kept the last drop down blank. 

Is there a way for users to first select how many columns they would like to select for join tool?

Sorry this is the first app I am trying to build. Let me know if my question is not clear.