What Is Data Type in Power Query?

What Is Data Type in Power Query?

Data type is a crucial concept in Power Query, a powerful data transformation and preparation tool in Microsoft Excel and Power BI. Understanding data types is essential for effectively manipulating and analyzing data. In this article, we will explore what data types are in Power Query and how they impact data operations.

What Are Data Types?

Data types define the nature of the values stored in a column or field. They provide important information about how the values should be interpreted, manipulated, and displayed. Data types play a crucial role in ensuring accurate calculations, sorting, filtering, and formatting of data.

Commonly Used Data Types

• Text: Represents alphanumeric characters such as names, addresses, or descriptions.
• Number: Represents numerical values like integers or decimals.
• Date/Time: Represents date and time values.
• Boolean: Represents logical values (True/False).

Data Type Detection

In Power Query, when importing or connecting to different data sources, the tool automatically detects the most appropriate data type for each column based on the source’s metadata. However, it is essential to review and validate these detected data types as errors can occur due to incorrect assumptions made by Power Query during detection.

You can verify and modify the detected data types using various techniques available in Power Query. Let’s explore some of them below:

The ‘Detect Data Type’ Feature

The ‘Detect Data Type’ feature allows you to manually specify the expected data type for a column. To use this feature:

1. Select the column(s) for which you want to specify the data type.
2. Right-click on the selected column(s) and choose ‘Change Type’.
3. Select the desired data type from the available options.

By using this feature, you can override the automatically detected data type with your preferred one, ensuring accurate data manipulation and analysis.

The ‘Data Type’ Column Property

The ‘Data Type’ column property allows you to explicitly set or modify the data type of a column. To access this property:

1. Select the desired column in Power Query Editor.
2. In the ‘Column Tools’ tab, find and click on the ‘Data Type’ dropdown list.
3. Select the appropriate data type from the available options.

This property is useful when you need to change or correct data types for specific columns manually. It provides fine-grained control over how Power Query interprets and handles values in each column.

Data Type Conversion

Power Query allows you to convert one data type into another using various functions and transformations. This is particularly helpful when dealing with incompatible data types in a single operation or when transforming values for specific calculations or visualizations.

To convert a column’s data type:

1. Select the desired column(s) in Power Query Editor.
2. In the ‘Transform’ tab, choose an appropriate conversion function such as ‘Number.FromText’, ‘Date.FromText’, etc., based on your requirement.

Using these conversion functions, you can easily change a text value into a numeric value or vice versa, make date/time calculations, and perform other necessary transformations.

Summary

Data types are fundamental in Power Query for accurate data manipulation and analysis. By understanding and managing data types effectively, you can ensure reliable calculations, correct sorting and filtering, and proper formatting of data. Use the ‘Detect Data Type’ feature, modify the ‘Data Type’ column property, and perform data type conversions to control how your data is interpreted and processed in Power Query.

By mastering the concept of data types, you can harness the full potential of Power Query to transform raw data into valuable insights.