What is ETL (extract, transform, load)?
ETL is the process of extracting data from source systems, transforming it into a clean and consistent shape, and loading it into a destination such as a data warehouse. A newer variant, ELT, loads first and transforms inside the warehouse.
Why it matters for your business
Reliable ETL is what makes reports trustworthy: it fixes formats, removes duplicates and applies business rules before anyone sees a number.
Each night, orders from the online store and invoices from the ERP are extracted, matched on order number and loaded into the warehouse for morning reports.