Daily DAX : Day 293 INFO.VARIATIONS

Explanation of the Power BI DAX Function INFO.VARIATIONS

The INFO.VARIATIONS DAX function is part of a category of DAX functions designed for analyzing a Power BI data model itself, rather than for performing typical business calculations. These functions are often referred to as "info functions" or "DMV functions" because they are based on Dynamic Management Views (DMVs) from Analysis Services.

What it Does

INFO.VARIATIONS returns a table that provides metadata about "variations" in the current data model. In the context of DAX and tabular models, a "variation" refers to a column that has different representations or roles. For example, a column might be used as a key for a relationship, a sort-by column, or a column in a hierarchy.

The returned table includes a variety of columns with information about these variations, such as:

• ID: The ID of the variation object.
• ColumnID: The ID of the column the variation is based on.
• Name: The name of the variation.
• Description: A description of the variation.
• IsDefault: A boolean value indicating if this is the default variation for the column.
• And many other columns providing detailed metadata.

Use Case

The primary use case for INFO.VARIATIONS and other INFO functions is model documentation and analysis for developers and BI professionals. It's not a function you would typically use in a measure or a calculated column for an end-user report. Instead, you would use it in a DAX query to get insights into the structure and properties of your model.

Here are some specific examples of how you might use INFO.VARIATIONS:

• Auditing and Documentation: You can use this function to programmatically generate a data dictionary or documentation for your model. This is especially helpful for large, complex models with many columns and relationships.
• Troubleshooting: If you're experiencing unexpected behavior, you can use INFO.VARIATIONS to inspect how a particular column is being used across the model, such as its role in different hierarchies or relationships.
• Automation: By using INFO.VARIATIONS in a DAX query, you could potentially automate tasks like identifying all columns that are used as a key in a relationship or finding columns that have multiple variations defined.

Important Considerations

• Developer-focused: INFO.VARIATIONS and other INFO functions are primarily for developers and modelers, not for creating end-user reports.
• Query View: These functions are best used in the DAX Query View in Power BI Desktop. You can also use them to create a calculated table, which can then be used for reporting and documentation purposes within the Power BI file itself.
• Permissions: Just like DMVs, using INFO functions might require certain permissions, such as model or workspace admin permissions.
• Deprecation: It's important to note that the use of some of the INFO functions, including INFO.VARIATIONS, is not recommended and is considered volatile or deprecated. It's best to consult the latest official Microsoft documentation and DAX guides for up-to-date information and any recommended alternatives.