In my viz I have 2 tables, Orders and Returns I have created a column called Order Id using Custom Split for Returns Table. Now I'm trying to join the Orders and returns table using the Order Id but Order Id doesn't show up in the join drop down. how do i go about from here to create a custom join calculation option.
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When you split a column, it shows up as a "Calculated field". If you want to join on something which is not in the primary data source then you might as well create it first and then load the data in Tableau.
You must have noticed though that the split columns show up when you move to a worksheet. In your case, you can simply join on the "Order ID" which is present in both data sets (Superstore data).
Hope this helps.
