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

Chapter 12: Differences Between DAX and M

M is the mash-up functional language of Power Query. Its formal name is Mashup or Power Query Formula Language, and it is used to query many data sources, while Data Analysis Expression (DAX) allows functions, much like Excel, to work on data stored in tables.

In this chapter, you will learn the differences between the two languages as we will look at the properties of both DAX and M. We will discuss the DAX syntax to understand how formulas are constructed, as well as look at how to add a DAX formula in Excel. Toward the end of the chapter, you will learn how to create a calculated column to display the result of a formula in a new column, and create a measure to calculate aggregates.

We will cover the following main topics in this chapter:

  • Learning about the DAX and M functionality
  • Constructing DAX syntax
  • Creating a calculated column
  • Creating calculated measures