An ETL testing mapping document contains,
- Columns mapping between source and target
- Data type and length for all columns of source and target
- Transformation logic for each column
The column mapping will be prepared by a business analyst or developer with the use of data model. The transformation rules will be defined by the business analyst based on the requirement from the end user.
It will be used as,
- Reference for development
- Reference for preparing test cases
- It will be used as future reference
It is a living document whenever any change comes that should be updated in the document.
A typical mapping document looks as below but the format may differ from organization to organization.
The below mapping is for moving address data from stage to data warehouse (EDW).
|ETL Job name||Job_address_stage_edv|
The below mapping is for moving employee data from stage to data warehouse (EDW).
|ETL Job name||Job_employee_stage_edv|