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Alteryx Designer Discussions

Find answers, ask questions, and share expertise about Alteryx Designer and Intelligence Suite.

Union Tool Crashing

7 - Meteor



I am trying to union together several (around 100) excel files into one file that I will eventually dump into a SQL table. The union tool works great but it incredibly slow. I cant even union more than 4 excel files to one tool without it taking about 10 minutes to respond (not even when I run the work flow, but just when I try to connect the input data to the union tool, once I go over four files to one tool it gets incredibly slow and I have to shut down the program).

Is there anything I should be doing differently or ways to make it run faster?


hi mrphilips27,


Are you bringing in each excel file individually and then connecting to the Union tool? If so, there might be a more efficient way to do this. I would recommend checking out this article to find out 3 methods to input multiple files at once:


Hope this helps!



8 - Asteroid

Have you "Enabled Performance Profiling" to make sure it is the Union tools?  




17 - Castor
17 - Castor

Hi @mphillips27,

You can also try this macro:!app/Read_All_Excel_Files/58dd51b3a18e9e18fca64172


In the past, I have used it to merge hundreds of files and it worked really well.

Give it a try and start with the same 4 files you have used.


Maybe you can also try moving them to a different location? Maybe it is working slowly because they are located in a location that is slowing everything down. I remember when I used Alteryx and box it wasn't working efficiently together.


Maybe check if moving the files to your desktop would speed up the process. 

7 - Meteor

Hi Everyone! I figured out my issue (although the wildcard feature works great and is a really awesome shortcut to know!) I forgot to set a range on the excel files I was using and it was taking in hundred of unnecessary columns hence why it was so slow. Once I set a range it works fine now! Thanks!