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

Power Query to the rescue

Now that we have created the relationships between our different tables, we will link these tables together. We will need to create a new field called NetIncome in our fRegionSales table. To keep the integrity of the data model, we cannot use Power Pivot to edit the existing data. However, we can create a new calculated column based on our existing data in the table.

Creating a calculated column

Click to select the fRegionSales tab. We are now going to add a column and create a calculated column. Double-click on the next available column on the right that states Add Column and add Net Income. Then, press Enter:

Figure 2.28 – Creating a new column name

Figure 2.28 – Creating a new column name

Looking at the preceding table, we may want to multiply the units and the discount, along with the unit price, which is in a different table. Normally, we would do a VLOOKUP in Excel to fetch this data. However, VLOOKUP does not exist in Power Pivot. Fortunately, there...