This is the number before applying join
This is the number after applying join
I wonder why the number after join is greater than the number before join. Does it because the join? I checked the result when I use summarize, the numbers are the same.
Here is my workflow
It means you have a many-to-many relationship in the join. Cartesian join in other words. Either your left/right anchor has values which are not unique as keys. Hence why your count is greater after than before.
I would suggest checking your logic again - I am assuming you are replicating a VLOOKUP - in Excel, VLOOKUPs only take the first value that appears, whereas Alteryx takes all that matches. So with that in mind, I would suggest reviewing it just before your Join or make the keys which are unique.
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