In the context of Informatica PowerCenter, mappings, sessions, and workflows are fundamental components that work together to execute data integration processes. Here's a breakdown of each:
1. Mapping :
- Definition:
- A mapping is the core design object in Informatica. It defines the flow of data from sources to targets.
- It specifies the transformations that data undergoes during its journey, such as filtering, sorting, joining, and aggregating.
- In essence, a mapping is a visual representation of the data transformation logic.
- Purpose:
- To define how data is extracted, transformed, and loaded.
- To implement business rules and data quality checks.
- To create a reusable data transformation logic.
2. Session :
- Definition:
- A session is an executable instance of a mapping.
- It contains the specific configuration settings required to run a mapping, such as database connections, file locations, and performance options.
- A session instructs the Informatica Integration Service on how to execute the data flow defined in a mapping.
- Purpose:
- To execute a mapping and move data from sources to targets.
- To define runtime parameters and configurations.
- To generate session logs that track the execution process.
3. Workflow :
- Definition:
- A workflow is a series of tasks that are executed in a specific order.
- It can include sessions, as well as other tasks such as email notifications, command executions, and file transfers.
- A workflow orchestrates the overall data integration process, managing the dependencies and execution order of tasks.
- Purpose:
- To automate complex data integration processes.
- To manage dependencies between tasks.
- To provide control over the execution flow.
- To enable scheduling, and monitoring of data integration processes.
In essence :
- The mapping defines what data transformations should occur.
- The session defines how the mapping should be executed.
- The workflow defines when and in what order the sessions and other tasks should be run.
These three components work in a hierarchical manner, with mappings forming the building blocks of sessions, and sessions being incorporated into workflows.
