Error DF-EXPR-010 in ADF data flow, Column 'body' used in expression is unavailable or invalid

Question

I need to take the results of a REST API query and transform them to upsert them into a table.

The source returns this JSON:

The Projection step ALWAYS puts the content in context of a body field. I can't figure out how to feed in the expected schema like I might in Power Automate.

Any step I put in after the source (flatten, derive, etc) fails with error DF-EXPR-010 stating that the column 'body' is unavailable. There is no body column. I'm at a loss. Help?

Answer 1

Apologies, wrong REST API source image, it should be:

still, no body column.

Answer 2

@Altobelli, Marie K

Thanks for reaching out to Microsoft Q&A.

I have reproduced from my end i can see all columns of my Json reflecting in derived column

please correct me if I missed any thing

could you please provide more details about source settings with screenshot and pipeline configuration

meanwhile please check the below steps and confirm whether it helps.

• Go to the Projection tab and define the complex type for the body column.
• Expand body and map the fields (e.g., result, ActivityStatusCode, CalendarId, etc.).
• Instead of referencing body.result directly, use:
• This helps ADF recognize the structure correctly.
• Since result is an array, use a Flatten transformation to extract its values before applying any derived columns or expressions.
• After importing the projection, check if the expected fields are accessible and correctly formatted.

I hope this information helps. Please do let us know if you have any further queries.

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