Workflow Parameters Overview
A workflow parameter is a constant value that you define before the workflow runs. Use workflow parameters to set values for tasks in the workflow or to set some user-defined mapping parameters. You can also use workflow parameters to set values for connection parameters or to set values for string parameters, such as configuration properties, command strings, or email addresses.
When you create parameters in a workflow, you can run a workflow with different parameter values. Parameters can reduce the overhead of creating multiple workflows when you need to change certain attributes of a workflow. All workflow parameters are user-defined parameters.
You can assign workflow parameters to task input and pass data from the workflow to the task. For example, you define a working directory parameter and assign the parameter to the Command tasks in the workflow.
You can also assign workflow parameters to user-defined mapping parameters in a Mapping task. For example, you define a workflow parameter that identifies the email address to send a notification email in a Notification task. Reference the workflow parameter in the recipients field for the Notification task.
You can override the value of a workflow parameter by including the parameter in a parameter set or a parameter file. A parameter set is a repository object that contains parameter values. You can deploy a workflow with a parameter set. A parameter file is an XML file that contains parameter values. A parameter file resides on the file system instead of in the repository. When you run a workflow, you can specify a specific parameter set or a parameter file for the workflow run.
Task Input
Task input is the data that passes into a task from workflow parameters and variables. The task uses the input data to complete a unit of work.
When you configure a task, you specify which workflow parameters and variables the task requires. The Data Integration Service copies the workflow parameter and variable values to the task when the task starts.
Mapping tasks, Command tasks, and Human tasks include an Input view to configure the workflow parameters and variables that the task requires. You can configure parameters for Mapping task configuration properties on the Input view.
You can reference workflow parameters for other tasks in different task views. For example, configure a workflow parameter that contains an email address in the Notification view of Notification task.
You can use workflow parameters in expressions in the conditional sequence flows from an outgoing gateway. The Data Integration Service evaluates the parameter values and identifies the object or objects to run next in the workflow.