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The Definitive Guide to Power Query (M)

You're reading from   The Definitive Guide to Power Query (M) Mastering complex data transformation with Power Query

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Product type Paperback
Published in Mar 2024
Publisher Packt
ISBN-13 9781835089729
Length 758 pages
Edition 1st Edition
Languages
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Authors (3):
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Greg Deckler Greg Deckler
Author Profile Icon Greg Deckler
Greg Deckler
Melissa de Korte Melissa de Korte
Author Profile Icon Melissa de Korte
Melissa de Korte
Rick de Groot Rick de Groot
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Rick de Groot
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Toc

Table of Contents (19) Chapters Close

Preface 1. Introducing M FREE CHAPTER 2. Working with Power Query/M 3. Accessing and Combining Data 4. Understanding Values and Expressions 5. Understanding Data Types 6. Structured Values 7. Conceptualizing M 8. Working with Nested Structures 9. Parameters and Custom Functions 10. Dealing with Dates, Times, and Durations 11. Comparers, Replacers, Combiners, and Splitters 12. Handling Errors and Debugging 13. Iteration and Recursion 14. Troublesome Data Patterns 15. Optimizing Performance 16. Enabling Extensions 17. Other Books You May Enjoy
18. Index

Null Values

A null value is used to represent the absence of a value, or a value of indeterminate or unknown state (i.e., in the case of a missing value).

Structure

A null value is written using the literal null.It is critical to note that null is different from 0. The former is the absence of a value, while 0 is a specific numerical value, just like 1 or 732.

Examples

if [Value] = null then “NA” else [Value]

Special Considerations

  • Equality Comparisons – Null has some unique properties with regard to how expressions involving the quality operator are evaluated. For example, null is only strictly equal to itself.
null = null    returns true
null = true     returns false
null = false    returns false
null <= null     returns null
null >= null     returns null
null <> null  returns null
null &lt...
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