Unable to map lookup activity output to Copy Activity Mapping in ADF

Question

I am new to the ADF.

While I am trying to use Copy activity for moving data from API Call output to Blob Json, I am unable to use Lookup output. I am trying to map the fields explicitly in Mapping using @item().SiteID. But JSON output returns only with input fields (not the derived fields). Can someone help me to let me know how to achieve this?

Can I use Copy activity in For Each activity (@activity('LookupAvailableChannelListForExport').output.value) to pass Lookup output value (@item().siteID)in mapping between source and sink?

Answer 1

As i know, the output of Look Up Activity can't be source data in copy activity,even mapping between source and sink. Acutally, Look Up activity prefers the following usage according to official document:

Dynamically determine which objects to operate on in a subsequent activity, instead of hard coding the object name. Some object examples are files and tables.

I think the example from above link is a good interpretation.You could see that the output of Look Up activity is configured as dynamic sql db source dataset table name.Not the data in source.

Then back to your requirement,i think you could configure the source dataset as root folder if the files are stored in the same directory with same schema. And keep this option is selected so that all the data in all files will be grabbed.

If you want to implement some variant of source data, copy activity can't cover it but data flow activity could.You could use Derived column.Such as resetting the Json structure.