Mapping Task Overview
A Mapping task runs a mapping in a workflow.
When you add a Mapping task to a workflow, you select a single mapping for the task to run. You can select any mapping that has physical data objects as input and output. When you change the mapping, the Model Repository Service tracks the effects of these changes on all Mapping tasks that include the mapping.
When you run a workflow, the workflow passes input data to a Mapping task in parameters and variables. The Mapping task uses the input data to run the mapping. When the task finishes running the mapping, the Mapping task passes output data back to the workflow in variables.
When you configure a Mapping task, you specify the input data for the task and the output data. You can set parameters that create a run-time context for the mapping task. Set task properties for the location and file name for the mapping log file. Set other properties at the mapping task level, such as the optimizer level, default sort order, and Java classpath.
After you configure a Mapping task, you can select a different mapping for the task to run.
Multiple Mapping Tasks that Run the Same Mapping
You can include multiple Mapping tasks that contain the same mapping in a single workflow.
When a workflow includes multiple Mapping tasks that contain the same mapping, you can configure the Mapping tasks to run the mapping differently. You can also assign a workflow parameter or variable to a user-defined mapping parameter in a Mapping task so that you can run the mapping with distinct parameter values.
For example, you add two Mapping tasks that each contain MappingA to a single workflow. You configure the first Mapping task to run MappingA with a connection to the Sales database. You configure the second Mapping task to run MappingA with a connection to the Finance database.