Hi @John K ,
Thanks for using Microsoft Q&A !!
If I understand correctly, you are trying to pass the parameters to a REST linked service while using it in a DataFlow.
In order to pass parameters to this linked service you need to set the Value of the parameter in your pipeline which actually calls this DataFlow. Please refer to the below screenshot -
Also, if you want to test your DataFlow then you need to pass the required parameters using Debug Settings of your DataFlow. Please refer to the below screenshot -
Please let me know if you have any questions.
Thanks
Saurabh
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