What is the CUSTOMDATA function in DAX?
The CUSTOMDATA function is a new addition to the DAX language that allows you to pass custom data to a Power BI visualization. This function is used in conjunction with the Custom Data Connector (CDC), which is a Power BI feature that allows you to connect to any external data source and retrieve data.
The CUSTOMDATA function takes a single argument, which is a string of custom data that you want to pass to your visualization. This custom data can be used to filter or modify the behavior of the visualization.
How to use the CUSTOMDATA function in DAX
To use the CUSTOMDATA function in DAX, you first need to create a Custom Data Connector (CDC). This involves writing a script that connects to your external data source and retrieves the required data.
Once you have created the CDC, you can use the CUSTOMDATA function to pass custom data to your visualization. To do this, you need to follow these steps:
1. Open the report page that contains the visualization you want to modify.
2. Select the visualization and click on the Format tab in the Visualizations pane.
3. Scroll down to the Custom Data section and click on the Edit button.
4. In the Custom Data Editor dialog box, enter the custom data string that you want to pass to the visualization.
5. Click on the OK button to save the changes.
Once you have passed the custom data to your visualization, you can use it to filter or modify the behavior of the visualization. For example, you can use the custom data to highlight specific data points, change the color scheme of the visualization, or modify the axis labels.
Best practices for using the CUSTOMDATA function in DAX
While the CUSTOMDATA function can be a powerful tool for enhancing your Power BI reports, there are some best practices that you should follow to ensure that you get the most out of this feature. Here are a few tips to keep in mind:
1. Use descriptive custom data strings: When passing custom data to your visualization, it’s important to use descriptive strings that clearly indicate the purpose of the data. This will make it easier to understand and modify the visualization later on.
2. Keep the custom data string simple: While it can be tempting to include a lot of information in your custom data string, it’s best to keep it simple. In general, you should include only the information that is necessary to modify the behavior of the visualization.
3. Use the custom data in a consistent manner: To ensure that your reports are easy to read and understand, it’s important to use the custom data in a consistent manner throughout your report. This will make it easier for users to understand the purpose and meaning of the custom data.
4. Test your custom data in different scenarios: Before finalizing your report, it’s important to test your custom data in different scenarios to ensure that it behaves as expected. This will help you catch any potential issues before they become a problem.
The CUSTOMDATA function in DAX is a powerful tool that allows you to pass custom data to your Power BI visualizations. By using this function, you can enhance the behavior and appearance of your reports, and make them more actionable. By following the best practices outlined in this article, you can ensure that you get the most out of this feature and create reports that are both informative and easy to understand.