What is Extract, transform, load (ETL)?
In short
Extract, transform, load (ETL) is the process of pulling data from source systems, cleaning and restructuring it, and loading it into a destination such as a data warehouse for analysis.
Key takeaways
- Transformation includes fixing formats, removing duplicates and joining tables.
- Controls should check that data is complete and accurate after each step, for example by reconciling record counts and totals.
- Poor ETL leads to unreliable analytics, however good the analysis.
Where it's tested
BAR: Data Analytics for Accounting — study notes, a five-minute revision sheet and practice questions.
Practise: 3 questions
Question 1 of 3 · 0 answered
In the ETL process used to prepare data for analysis, the transformation stage involves: