Data issue union with an empty input

[Cutugnos]

Hi everyone,

We're encountering an issue during the implementation of a workflow and would appreciate your insights.

Context:
We're pulling data from two tables (MARA and MAKT). Occasionally, one of the two input of the union may be empty. When this happens, the Union tool's output is also empty, and the workflow fails to populate the expected data downstream.

We've tried a few workarounds:

• Using the CacheDataset Macro to materialize the data in Alteryx's cache. However, this requires running the workflow twice, which is not ideal given its complexity and runtime.
• Disabling AMP engine or using an Action tool to cache the dataset in a temporary folder. Unfortunately, these approaches still result in an empty output unless both input streams to the Union tool are populated.

We're looking for a more efficient solution that allows the workflow to handle cases where one of the input tables is empty, without compromising the output or requiring multiple runs.

I've attached a screenshot to help illustrate the issue. There are also some try and workaround we tried!

Thanks in advance for any suggestions or ideas!

 

[MinhLO]

@Cutugnos , based on your latest screenshot, it seems the issue is not with the union but with the tool right after.

what is the error message?

From what I guess - but lacking elements here - you are missing some columns from one of the two summarize, and randomly as you do not know which part of your workflow will have some.

Then what I would suggest is that you 'Ensure Fields' .

For that, create an input text with no rows, and columns names = all your column names from summarize one and two. (do not forget a select after to cast the correct data types)

Union this to your data. This will Ensure all your Fields are present, even if there is no data coming from one summarize.

Please try this - otherwise I need more details (error message, full picture of the workflow) to better understand your problem

[anabel1224]

Hola me pasaba el mismo problema , me funcionaba al correrlo localmente pero al cargarlo al servidor me salía ese error . Lo que hice fue desactivar en Runtime el "Use AMP Engine" y funcionó

[jrlindem]

@anabel1224's message:

"Hello, I was having the same problem, it worked when running it locally but when I uploaded it to the server I got that error. What I did was disable the 'Use AMP Engine' in Runtime and it worked."