Introduction to BarChart v1.5 Visual

Power ON’s BarChart is a custom visual designed for Microsoft’s Power BI. It enhances the user experience by enabling end users to make permanent changes to data through write-back functionality. This means users can target measures and DAX expressions to modify data directly within their reports. The BarChart section in the help provides a detailed overview of how to use this tool effectively. It covers common use-case implementations, proper configuration, and strategies for overcoming potential pitfalls.

This topic caters to both technical experts (such as developers, DBAs, and BI professionals) who have in-depth knowledge of SQL Server, SSAS Tabular models, Azure Services, and Power BI, as well as users who primarily concentrate on creating and preparing reports using Power BI Desktop.

Power ON’s BarChart enables users to modify figures that result from DAX expressions defined aggregations. In traditional dimensional modeling, these aggregations are calculated on fact tables, with the calculation context defined by dimensions that are in relation with the fact table. BarChart enables users to update the results of their measures.

Key features of BarChart include:

• Writing back values to the underlying data source.
• Modifying figures by using drag-and-drop interactions on data points.
• Changing the ratio of data points while maintaining total values.
• Creating comments on data points.

Following is the high-level overview of how write-back works for Tabular models. Depending on your data source (SSAS In-Memory, SSAS Direct Query, or SQL only) Power ON’s write-back service performs the following steps:

1. The service captures the modified value along with its tuple (the intersection of dimensions used in the calculation of measure for the given cell) and the user context. Based on the SSAS model structure (relationships, table queries, and measure definitions) the service composes T-SQL statements for execution.
2. It executes the compiled T-SQL statement against the underlying data source (fact table) to save the modifications.
3. For SSAS in-memory models, the service reprocesses the table. See Performance Optimization for more information.
4. It refreshes the visual to display the changes in the report.

Limitations

As with all custom visuals developed for Power BI, BarChart has the following limitations due to Microsoft's policies:

• Renaming columns and tables within the Power BI report is not supported. These names must match those used in the underlying data source. For SSAS models, the names should align with the entities visible in your model or the report’s Fields sections.
• The characters '[' and ']' (brackets) are not supported in measure names.
• The character '.' (dot) is not supported in table names, although it can exist in schema names. If your table name contains unsupported characters, consider creating a view on top over the table that adheres to the required format and use that view for write-back functionality.
• You can only display 5000 records at once, it is the default value set by Microsoft.
• The DAX Expression COUNTROWS(Table) is not supported for write-back.
• Non-writable views that serve as a data source for fact tables are not supported for write-back. Consider materializing your view into a physical table or simplifying the view’s complexity. Alternatively, you can create INSTEAD OF INSERT | UPDATE triggers to handle the operation. Typically, non-writeable views are views that contains complex SQL queries with multiple joins, CASE statements in WHERE clauses, CTEs (Common Table Expressions), and aggregations. You can test your view by duplicating it under a different name and executing an INSERT statement against it.
• If you’re using the on-premises Power BI Report Server, ensure you have at least the January 2019 version, along with Power BI Desktop 2019 January or more recent versions.
• When using slicers, page-level, report-level, or visual-level filters, it is essential to also incorporate the SmartFilter helper visual. See Importance of SmartFilter Helper Visual for more information.

Versions

While this help primarily covers the latest version of BarChart, you can still utilize previous versions included in the setup kit. However, some features detailed here may not be available in older versions.

The most recent visual is BarChart v1.5.1.pbiviz. To download different versions, follow these steps:

1. Visit the store.poweronbi.com site and register using the same domain name you originally used.

2. Log in to the site and select the Visuals tab.



3. Explore the available versions of our write-back capable visuals.



4. Select the desired version of BarChart and click Download.
Note:

You can also download the release notes specific to the BarChart version you are downloading.

Upgrading from an Older Version of BarChart to v1.5.1

Follow the steps below to upgrade from an older version of BarChart to version 1.5.1:

1. Download the latest version of BarChart from the provided URL.
2. Open a BarChart-related report and download the .pbixfile by selecting File > Download the .pbix file option.
3. Rename the downloaded report to preserve the original version and then open the file in PowerBI Desktop.
4. Click on the three dots in the Visualizations pane.
5. Select Import a visual from a file and then select Import.
6. Locate the downloaded visual file (barChart_v1.5.1.pbiviz), likely saved in your Downloads folder in File Explorer. Click to select it and then click Open.
7. You will receive a notification once the import is successful. Click OK.
   
8. Right-click on the visual icon and select About from the menu. A pop-up window will provide details, including the version number.
   

   

9. Select the BarChart visual in your report and click on the Power ON BarChart icon (version 1.5.1). The visual in the report will update to the newer version while retaining your previous settings.