Tableau is a powerful data visualization and business intelligence tool that allows users to connect to various data sources, analyze data, and create interactive visualizations. Here are some advanced features in Tableau:

1. Tableau Prep: Tableau Prep is a data preparation tool that allows you to clean, shape, and combine data from different sources before visualizing it in Tableau. It helps streamline the data preparation process and makes it easier to work with messy or complex datasets.

2. Calculated Fields: Tableau allows you to create custom calculations using calculated fields. These calculations can be simple arithmetic operations or more complex formulas involving conditional statements, logical operators, and functions. Calculated fields give you greater flexibility in data analysis and visualization.

3. Level of Detail (LOD) Expressions: LOD expressions enable you to perform calculations at different levels of granularity without changing the view’s level of detail. You can use FIXED, INCLUDE, and EXCLUDE keywords to define the scope of your calculations and gain more control over aggregations.

4. Tableau Extensions: Extensions are add-ons that expand Tableau’s functionality by integrating external web applications or custom visualizations. You can use extensions to include additional features like advanced mapping, custom layouts, and enhanced interactivity.

5. Parameter Actions: Parameter actions allow you to create dynamic interactions in your dashboards. By linking parameters to various elements, such as filters, calculations, or data source connections, users can control the dashboard’s behavior and customize their visualizations.

6. Data Blending: When working with multiple data sources, Tableau offers data blending, which enables you to combine data from different databases or files without the need for data modeling or complex joins.

7. Advanced Analytics: Tableau supports a variety of advanced statistical and predictive analytics functions through integration with R, Python, and other statistical tools. This allows you to perform complex analyses and create advanced visualizations based on predictive models.

8. Dashboard Actions: Dashboard actions enable you to create interactive dashboards by linking sheets and visualizations together. Users can filter, highlight, or navigate through the data by interacting with various elements on the dashboard.

9. TabCMD and Tableau Server REST API: For automation and integration with other systems, Tableau provides command-line tools (TabCMD) and a REST API that allow you to programmatically manage and publish Tableau content on Tableau Server.

10. Custom SQL: If you need to work with complex queries or specific data transformations, you can use Custom SQL to write your own SQL statements directly within Tableau.