Book Image

Learn Power Query

By : Linda Foulkes, Warren Sparrow
Book Image

Learn Power Query

By: Linda Foulkes, Warren Sparrow

Overview of this book

<p>Power Query is a data connection technology that allows you to connect, combine, and refine data from multiple sources to meet your business analysis requirements. With this Power Query book, you’ll be empowered to work with a variety of data sources to create interactive reports and dashboards using Excel and Power BI. </p><p>You’ll start by learning how to access Power Query across different versions of Excel and install the Power BI engine. After you've explored Power Pivot, you’ll see why Excel users find it challenging to clean data in Power Pivot and learn how Power Query can help to tackle the problem. The book will show you how to transform data using the Query Editor and write functions in Power Query. A dedicated section will focus on functions such as IF, Index, and Modulo, and creating parameters to alter query paths in a table. You’ll also work with dashboards, get to grips with multi-dimensional reporting, and create automated reports. As you advance, you'll cover the M formula language in Power Query, delve into the basic M syntax, and write the M query language with the help of examples such as loading all library functions offline in Excel and Power BI. Finally, the book will demonstrate the difference between M and DAX and show how results are produced in M. </p><p>By the end of this book, you’ll be ready to create impressive dashboards and multi-dimensional reports in Power Query and turn data into valuable insights.</p>
Table of Contents (17 chapters)
Free Chapter
1
Section 1: Overview of Power Pivot and Power Query
6
Section 2: Power Query Data Transformations
11
Section 3: Learning M

Learning about the DAX and M functionality

In this section, you will learn the differences between DAX and M and find out when each one is used, as well as their functions.

DAX is mainly used in data transformations in Power BI dashboards where you would need to gain business analysis from existing data models. DAX is powerful when required to produce, for instance, growth percentage analysis across a list of products for specific date ranges, or to analyze market trends. Together with Power BI, DAX can powerfully assist with real-world business challenges to create meaningful, interactive business dashboards for reporting and decision-making. It is a formula language; it is not considered a programming language as it is structured using custom calculations (in fields and columns). As a formula language, DAX comprises an assembly of the following:

  • Operators
  • Constants
  • Functions

Now, M code is used in the Power Query editor. Each time you create a transformation...