Problems with Data Factory 'Flatten' option

Question

I am trying to use Flaten inside of Data Factory, I keep on getting the error

The inner value type of the 'Unroll by' structure '{Category Numbers}' must be array type (e.g. structue of arrays, array of arrays)

Whilst I just did a 'Split' operation, this is the preview of the column 'Cateogry Numbers' from the previous step.

Does anybody have any idea why this is happening?

Answer 1

Hi @Adrian ,

Thanks for using Microsoft Q&A forum and posting your query.

We have noticed that one of our engineer has already been engaged on the same query in Stackoverflow and shared few inputs on Flatten transformation : Data Factory not recognising array for 'flatten' operation

If you still have further queries, please do share a sample of your input/source data (pls remove sensitive information) and expected output so that we can further assist as needed.

Thank you

----------

• Please accept an answer and up-vote if it helps. Original posters help the community find answers faster by identifying the correct answer. Here is how.
• Want a reminder to come back and check responses? Here is how to subscribe to a notification.