DAX, or Data Analysis Expressions, is a formula language used in Microsoft Power BI, Excel Power Pivot, and SQL Server Analysis Services (SSAS). It is designed to work with data modeling and analytics, allowing users to create custom formulas for data manipulation and analysis. DAX functions are used to create custom calculated columns, tables, and measures in these tools.
Key features of DAX include:
- Formulas: DAX allows users to create custom formulas to perform calculations on data in Power BI, Excel, and SSAS. These formulas can be used for aggregations, filtering, and manipulating data.
- Data Modeling: DAX is closely associated with data modeling concepts, such as creating relationships between tables, defining calculated columns, and building measures for analysis.
- Row and Filter Contexts: DAX formulas are designed to handle both row context (calculations at the individual row level) and filter context (calculations considering filters applied to data).
- Aggregation Functions: DAX includes a variety of aggregation functions, such as SUM, AVERAGE, MIN, MAX, and others, that can be used to summarize and aggregate data.
- Time Intelligence Functions: DAX provides specific functions for handling time-based calculations, making it powerful for working with date and time dimensions in business intelligence scenarios.
- Statistical Functions: DAX includes statistical functions that enable users to perform various statistical analyses on their data.
- Filter Functions: DAX allows users to create complex filters using functions like CALCULATE and FILTER, which are crucial for controlling the context in which calculations are performed.
- Integration with Power BI: DAX is a key component of the Power BI platform, enabling users to create dynamic and interactive reports and dashboards.
