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Introducing Power Query
IN THIS CHAPTER
Understanding Power Query basics
Understanding query steps
Managing existing queries
Getting an overview of query actions
Getting data from external sources
Managing data source settingsI
n information management, ETL refers to the three separate functions typically required to inte-
grate 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 their reporting. This amounts to lots of manual effort.Power Query enhances the ETL experience by offering an intuitive mechanism to extract data from
a wide variety of sources, perform complex transformations on that data, and then load the data
into a workbook or the internal data model.In this chapter, you’ll explore the basics of Power Query and get a glimpse of how it helps you save
time and automate the steps needed to ensure that clean data is imported into your reporting
models.Understanding Power Query Basics
To start this basic look at Power Query, let’s walk through a simple example. Imagine that you need
to import Microsoft Corporation stock prices for the past 30 days using Yahoo Finance. For this sce-
nario, you need to perform a web query to pull the data needed from Yahoo Finance.To start your query, follow these steps:Excel® 2019 Bible, First Edition. Michael Alexander, Dick Kusleika and John Walkenbach.
© 2019 John Wiley & Sons, Inc. Published 2019 by John Wiley & Sons, Inc.