Which Power BI function aids in making calculations more efficient and readable?

The use of variables in Power BI helps enhance both the efficiency and readability of calculations. By defining variables within DAX (Data Analysis Expressions) formulas, you can store intermediate results and use them multiple times throughout your expressions. This not only reduces the need for repeated calculations, which can significantly optimize performance, but it also makes the overall formula clearer and easier to understand.

When you assign a value to a variable, you can use that variable instead of recalculating the same expression multiple times. This is particularly beneficial when performing complex calculations, as it simplifies the formula and makes it easier for others (or yourself in the future) to read and understand what the calculation intends to achieve. Additionally, named variables help create self-documenting formulas that indicate the meaning of the data being manipulated.

In contrast, calculated columns are useful for adding additional data to a table but don’t inherently improve efficiency or readability within complex calculations. Summarization is a technique used for aggregating data but lacks the direct structural clarity that variables provide. Queries allow you to retrieve and manipulate data from various sources but do not directly contribute to the efficiency and readability of DAX calculations. Hence, the focus on using variables is what makes this option the strongest choice for enhancing both performance and clarity