I am passing in a parameter of type string into an ADF Data flow. I have a derivied column and I am trying to set that column value to the parameter value. However, I keep getting an error Column 'ClientA' used in expression is unavailable or invalid. For column it is showing the value of the parameter. In debug, I have to wrap the parameter value in single or double quotes for it to work. I do not know how to make the dataflow derived column value interpret the parameter as a string inside the expression. I've tried concatenating the parameter with stings or double quotes but it still doesn't work. ParameterName: ClientName ParameterValue: ClientA ParameterType: String

I also have another derived column of type int, but that one is mapping without issue.

I am passing in a parameter of type string into an ADF Data flow. I have a derivied column and I am trying to set that column value to the parameter value. However, I keep getting an error Column 'ClientA' used in expression is unavailable or invalid. For column it is showing the value of the parameter. In debug, I have to wrap the parameter value in single or double quotes for it to work. I do not know how to make the dataflow derived column value interpret the parameter as a string inside the expression. I've tried concatenating the parameter with stings or double quotes but it still doesn't work. ParameterName: ClientName ParameterValue: ClientA ParameterType: String

I also have another derived column of type int, but that one is mapping without issue.

• azure-data-factory
• google-cloud-dataflow

• Can you provide the exact expression in your derived column and where are you getting the error? During the dataflow run from pipeline run or during the debug run of the dataflow? – Rakesh Govindula Commented Jan 18 at 20:25
• The expression in the screenshot above is the exact expression. I get the same error when I debug the dataflow and when I debug the pipeline that uses the dataflow. – chwanhun Commented Jan 18 at 21:49
• Let me try from my end and I will update you. – Rakesh Govindula Commented Jan 19 at 10:10

1 Answer 1

You need to use the dataflow parameters in the derived column as show below.

First create the required parameter in the dataflow with required type.

Give the parameter to the columns in the derived column transformation.

If you want to test the data preview inside the dataflow, go to the debug settings and provide the value for the parameter.

If you want to pass the parameter value from the pipeline, you need select pipeline expression here and give your string as shown below. You can update the value like concatenation with any other strings here using pipeline expression.

Now, run the dataflow from the pipeline and it will show the parameter value in the dataflow activity input.

I have opted for the sink cache and you can see the sink results in the dataflow activity output.