CHAPTER 38
Introducing Power Query
In information management, ETL refers to the three separate functions typically required to integrate disparate data sources: extraction, transformation, and loading. The extraction function refers to the reading of data from a specified source and extracting a desired subset of data. The transformation function refers to the cleaning, shaping, and aggregating of data to convert it to the desired structure. The loading function refers to the actual importing or writing of the resulting data to a target location.
Excel analysts have been manually performing ETL processes for years—although they rarely call it ETL. Every day, millions of Excel users manually pull data from some source location, manipulate that data, and integrate it into...
