Unroll By button for flatten is grayed out

Chuck Roberts 65 Reputation points

I'm new to Azure Data Factory. In Azure Data Factory I have an XML file I want to flatten and convert to a CSV file. I add a Data Flow, and to the Data Flow I add a "source1" where I have already done an "Import projection". I added a "flatten1". In the flatten1 Settings I have to choose a field to "Unroll By" but all fields in my XML file are grayed out.

  1. How do fix this so I can choose an Unroll by?
  2. Could there be something wrong with my XML file? I got no errors about it from Azure.

When I publish the pipeline I get this error:


The following column(s) have a complex structure which can only be written to Snowflake, REST, ORC, JSON, AVRO, and Azure Cosmos DB: 'Order'. Please remove the columns or update the sink to Snowflake, REST, ORC, JSON, AVRO, or Azure Cosmos DB."

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Azure Data Factory
An Azure service for ingesting, preparing, and transforming data at scale.
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  1. BhargavaGunnam-MSFT 28,931 Reputation points Microsoft Employee

    Hello Chuck Roberts,

    The flatten transformation unrolls an array. Hence, the unroll root must be an array of complex objects.

    The possible root cause is that your complex object type is not an array.

    You can refer the below document for more information about the flatten transformation requirement.


    I hope this answers your question.