Daily DAX : Day 264 INFO.STORAGEFILES

 The **INFO.STORAGEFILES** function in Power BI's Data Analysis Expressions (DAX) is part of the **INFO functions** family, introduced to provide metadata about a Power BI semantic model's storage. Specifically, **INFO.STORAGEFILES** retrieves information about the storage files associated with the data model, which can be useful for analyzing and optimizing the model's performance, particularly in terms of storage usage and efficiency.

### Overview

- **Purpose**: The **INFO.STORAGEFILES** function returns a table containing metadata about the storage files used by the Power BI semantic model. This includes details such as file names, sizes, and other storage-related attributes.

- **Category**: INFO functions (based on Dynamic Management Views (DMVs) from Analysis Services, adapted for DAX).

- **Output**: Returns a table data type, which can be used with other DAX functions like `FILTER`, `SELECTCOLUMNS`, or `ADDCOLUMNS` for further analysis.

- **Permissions**: Requires **semantic model admin permissions** to access this function, and some scenarios may also require **workspace admin permissions**.[](https://learn.microsoft.com/en-us/dax/info-functions-dax)

### Syntax

```dax

INFO.STORAGEFILES()

```

- **Arguments**: This function takes **no arguments**.

- **Return Value**: A table with columns describing the storage files in the semantic model. The exact columns returned may include details like file name, size, type, and other metadata, though the specific schema depends on the Power BI implementation.

### Usage

The **INFO.STORAGEFILES** function is primarily used in **DAX Query View** in Power BI Desktop to explore and document metadata about the model's storage files. It cannot be used directly in calculated columns, measures, or calculated tables due to its tabular output and restrictions.[](https://datasturdy.com/dax-query-view-dmvs-for-power-bi-model-using-dax-functions/)

To use it:

1. Open **DAX Query View** in Power BI Desktop.

2. Write a query like:

   ```dax

   EVALUATE

   INFO.STORAGEFILES()

   ```

3. Run the query to retrieve a table with details about the storage files.

Alternatively, you can create a **calculated table** to store the results for reporting purposes:

```dax

StorageFilesTable = INFO.STORAGEFILES()

```

### Practical Use Case

- **Model Optimization**: By analyzing the output of **INFO.STORAGEFILES**, you can identify which storage files consume the most space in your semantic model. This can help in optimizing the model by reducing unnecessary data, adjusting compression settings, or removing redundant objects.[](https://radacad.com/power-bi-model-analysis-using-dax-info-functions/)

- **Documentation**: The function aids in documenting the storage structure of your Power BI model, which is useful for auditing or sharing model details with a team.[](https://powerbi.microsoft.com/en-us/blog/dax-query-view-introduces-new-info-dax-functions/)

### Example

Suppose you want to check the storage files in your Power BI model to identify large files that might be impacting performance. You can run:

```dax

EVALUATE

INFO.STORAGEFILES()

```

This query might return a table with columns such as:

- **FileName**: The name of the storage file.

- **FileSize**: The size of the file (in bytes or another unit).

- **FileType**: The type of file (e.g., data, metadata).

- **LastModified**: The last modification date of the file.

You could extend this query to filter or format the results, for example:

```dax

EVALUATE

SELECTCOLUMNS(

    INFO.STORAGEFILES(),

    "File Name", [FileName],

    "Size (MB)", [FileSize] / (1024 * 1024)

)

```

This formats the file size in megabytes for easier interpretation.

### Key Characteristics

- **Tabular Output**: Like other INFO functions, **INFO.STORAGEFILES** returns a table, making it compatible with DAX functions that operate on tables (e.g., `FILTER`, `ADDCOLUMNS`).[](https://learn.microsoft.com/en-us/dax/info-functions-dax)

- **Based on DMVs**: The function is derived from the Dynamic Management Views (DMVs) used in Analysis Services, but it’s adapted to work natively in DAX, eliminating the need for SQL-like syntax.[](https://powerbi.microsoft.com/en-us/blog/dax-query-view-introduces-new-info-dax-functions/)

- **Limitations**: 

  - Not supported in SQL Server Analysis Services, Azure Analysis Services, or PowerPivot models—only in Power BI semantic models.[](https://learn.microsoft.com/en-us/dax/info-functions-dax)

  - Cannot be used in measures, calculated columns, or calculated tables directly due to its tabular nature and permission requirements.[](https://datasturdy.com/dax-query-view-dmvs-for-power-bi-model-using-dax-functions/)

- **IntelliSense Support**: In DAX Query View, typing `INFO.` will show **INFO.STORAGEFILES** in the IntelliSense dropdown, making it easy to discover.[](https://powerbi.microsoft.com/en-us/blog/dax-query-view-introduces-new-info-dax-functions/)

### Notes

- **Performance Analysis**: This function is particularly useful for Power BI developers or administrators looking to optimize model size and performance by identifying large storage files.[](https://radacad.com/power-bi-model-analysis-using-dax-info-functions/)

- **DAX Query View**: The best way to test and explore **INFO.STORAGEFILES** is through DAX Query View, as it allows you to see the tabular output directly before incorporating it into a calculated table.[](https://radacad.com/power-bi-model-analysis-using-dax-info-functions/)

- **Documentation**: For detailed metadata analysis, you can combine **INFO.STORAGEFILES** with other INFO functions like `INFO.TABLES` or `INFO.MEASURES` to get a comprehensive view of the model.[](https://powerbi.microsoft.com/en-us/blog/dax-query-view-introduces-new-info-dax-functions/)

### Additional Resources

- **Microsoft Learn**: For more details on INFO functions, see the [DAX function reference](https://learn.microsoft.com/en-us/dax/info-functions-dax).[](https://learn.microsoft.com/en-us/dax/info-functions-dax)

- **RADACAD**: For practical examples of using INFO functions for model analysis, check [Power BI Model Analysis using DAX INFO Functions](https://radacad.com).[](https://radacad.com/power-bi-model-analysis-using-dax-info-functions/)

- **Power BI Blog**: Learn about the introduction of INFO functions in the [Power BI DAX Query View blog post](https://powerbi.microsoft.com).[](https://powerbi.microsoft.com/en-us/blog/dax-query-view-introduces-new-info-dax-functions/)

By leveraging **INFO.STORAGEFILES**, Power BI users can gain deeper insights into their model's storage structure, aiding in optimization and documentation efforts.