In order to pass dynamic values to a linked service, we need to parameterize the linked service, the dataset, and the activity.
I have a pipeline where I log the pipeline start to a database with a stored procedure, lookup a username in Key Vault, copy data from a REST API to data lake storage, and log the end of the pipeline with a stored procedure. My username and password are stored in separate secrets in Key Vault, so I had to do a lookup with a web activity to get the username. The password is retrieved using Key Vault inside the linked service. Data Factory doesn’t currently support retrieving the username from Key Vault so I had to roll my own Key Vault lookup there.
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