How Analysts Translate Messy Data, DAX and Dashboard into Action using Power BI

Source: Dev.to

Data Cleaning in Power BI

Some basic tasks include:

• Removing duplicates
• Handling missing values
• Data type conversion
• Replacing values

DAX – Data Analysis Expressions

DAX is a set of functions for calculations. After cleaning your data, you can perform calculations to create tables or columns.

Common DAX Functions

• Simple aggregations: COUNT, SUM, AVERAGE, MIN, MAX
• Logical: IF (returns different values based on true/false)
• Date difference: DATEDIFF (difference between two dates in days, months, years)
• Iterator functions: SUMX, AVERAGEX, COUNTX

Row Context and Filter Context in DAX

Row Context

Operates on a row‑by‑row basis. Examples include iterator functions such as SUMX and AVERAGEX.

Filter Context

Refers to the set of filters applied to the data model before calculations. A typical function that introduces filter context is CALCULATE.

Dashboards

A dashboard is a page that tells a story through visuals. It provides highlights at a glance, giving a general view of the output without deep diving, which can support decision‑making.

Power BI is key for decision making. It helps businesses make sense of data, answer “what” and “why” questions, and inspire the next steps.