How to create ETL Test Case
ETL testing is a concept which can be applied to different tools and databases in information management industry. The objective of ETL testing is to assure that the data that has been loaded from a source to destination after business transformation is accurate. It also involves the verification of data at various middle stages that are being used between source and destination.
While performing ETL testing, two documents that will always be used by an ETL tester are
- ETL mapping sheets :An ETL mapping sheets contain all the information of source and destination tables including each and every column and their look-up in reference tables. An ETL testers need to be comfortable with SQL queries as ETL testing may involve writing big queries with multiple joins to validate data at any stage of ETL. ETL mapping sheets provide a significant help while writing queries for data verification.
- DB Schema of Source, Target: It should be kept handy to verify any detail in mapping sheets.