What is ETL: Extract, Transform and Load?
Extract, transform, load (ETL) allows you to prepare data for analysis by combining data from internal and external sources, transforming it into a common format, and loading it into a database or data warehouse. ETL prepares your data in the three steps outlined above:
- Extract reads data from a data source and extracts the desired subset of data from the source.
- Transform uses the extracted data and uses rules to convert the acquired data into a common format.
- Load writes the resulting data into a data warehouse or data mart.
Why use an ETL tool?
You are always able to report against any of your data sources, but large volumes of data and data diversity are important considerations– this is where ETL becomes desirable. As your data sources diversify and volume of data grows, you will want to consider integrating your data from all your data sources. This will allow you to have increased data consistency, and the ability to report on a diverse data set for a more holistic answer to your business questions.