Chapter 2: Introducing ETL
When I first started in the data warehousing business, something like 20 years ago, I was asked in an interview to define ETL. Being at my first job interview, I had no clue what the interviewer meant by ETL. Luckily, the interviewer kind of liked me and hired me anyway. He told me that I would know all about ETL quite soon. Being in data warehouse businesses for many years, and more recently a data engineer, ETL is what has kept me busy most of the time since then.
ETL stands for Extract, Transform, and Load. ETL is a data moving technique that has been used in various forms since the first enterprise data warehouses' inceptions.
Microsoft formalized the ETL concept near the end of the 1990s with a tool called DTS: Data Transformation Service. This ETL tool, aimed at helping database administrators load data into and from SQL Server, used SQL and ActiveX to move and transform data on-premises.
Microsoft brought its ETL tool to the cloud with...