DAX (Data Analysis Expressions)
DAX (Data Analysis Expressions) is a formula language used in Microsoft Power BI, Analysis Services, and Power Pivot in Excel for data modeling and analysis. It enables users to create custom calculations, aggregations, and business logic on data models, primarily working with tabular data in relational models. DAX is designed to handle time intelligence, filtering, and complex calculations in a user-friendly syntax similar to Excel formulas.
Developers should learn DAX when working with Microsoft's business intelligence tools like Power BI or Analysis Services to build advanced data models and reports. It is essential for creating calculated columns, measures, and tables that support dynamic analytics, such as year-over-year comparisons, running totals, and custom KPIs. Use cases include financial reporting, sales dashboards, and operational analytics where real-time data insights are required.