Incorrect Join Results using AMP Engine

[jvaucher0804]

Hello! 

I have a large workflow that combines multiple disparate data sources using an union tool. After the union, I join the union result with a date master table to get all the data on the same shipping day schedule. The workflow worked great using the original engine but after upgrading to 2020.4 and enabling the AMP engine, I am getting weird results. I've posted a sample image of the output in Tableau below.

The result should show shipping day 1 as it's all the data for the 1st of the month but as you can see it shows varying results.

Any thoughts, insight and or feedback would be greatly appreciated.

Thanks so much!

[RishiK]

@jvaucher0804 what does your workflow look like.

It is common that the way the data is processed with AMP will be different to non AMP.

https://help.alteryx.com/current/designer/alteryx-engine-and-amp-main-differences

[mbarone]

Because AMP distributes processing to multiple threads, and then brings the data back together, it may not be in the same order as when using non-AMP.  The data set that results should be the same, meaning you shouldn't be losing or gaining any records using AMP vs. non-AMP.  Nor should the values of your fields be different.  The order of those records, however, will be different.

Are you saying that you're losing (or gaining) records?  Are the values different?  Or is it just the order?

[jvaucher0804]

Thanks for this - helped me do some more research on this and found it was because I wasn't doing a sort after calculating a running total.

Should have done more research! Thanks anyways!

[mbarone]

Sure thing!

[marinamaller]

I'm having a similar issue using a simple Summarize. While I can add a sorting tool after, it is pretty annoying that the system cannot do it by itself. For some processes, adding a sorting tool after each summary would greatly undo the time-savings of using the AMP engine. I hope they add a feature to the Summarize tool with AMP engine that automatically sorts results the same way the non-AMP engine would be.

[TonyaS]

Thanks all for your feedback and for using the new AMP Engine. 

We are working hard to address issues that our customers are finding now that AMP is available.

It is true that the record order will sometimes vary when using AMP Engine for certain tools. The explanation is listed in our documentation here about the differences between original Engine and AMP: https://help.alteryx.com/current/designer/Alteryx-Engine-and-AMP-Main-Differences

Since you are trying out the AMP Engine, I also wanted to share 

some helpful links to available documentation about AMP Engine:

https://help.alteryx.com/current/designer/alteryx-amp-engine

https://help.alteryx.com/current/designer/Alteryx-Engine-and-AMP-Main-Differences

https://help.alteryx.com/current/designer/AMP-Memory-Use

https://help.alteryx.com/current/designer/tool-use-amp

https://community.alteryx.com/t5/Analytics/Accelerate-Your-Analytic-Processes-with-the-New-AMP-Engin...

https://community.alteryx.com/t5/Engine-Works/AMPlify-your-Workflows/ba-p/617590

https://community.alteryx.com/t5/Alteryx-Designer-Discussions/Best-practice-with-the-new-Multi-threa...

AlterEverything Podcast: https://community.alteryx.com/t5/Alter-Everything-Podcast/66-The-Alteryx-AMP-Engine-Explained/ba-p/5...

https://community.alteryx.com/t5/Engine-Works/AMP-Engine-Technical-Deep-Dive-Part-1-Why-AMP/ba-p/570...  

https://community.alteryx.com/t5/Engine-Works/AMP-Engine-Technical-Deep-Dive-Part-2-Key-concepts-of-...