ETL is nothing but Extraction, Transformation, and Loading. a ETL Developer(those who are expertise in dwh extracts data from heterogeneous databases(or)Flat files, Transform data from source to target(dwh) while transforming needs to apply transformation rules and finally load data into dwh.
There are several ETL Tools available in the market those are
- Data stage
- Oracle Warehouse Builder
- Bodi (Business Objects Data Integration)
- MSIS (Microsoft Integration Services) etc