Understanding Data Modeling in Power BI: Joins, Relationships, and Schemas Explained

Introduction Last week in our Power BI class we focused on one of the most important concepts in data analysis: data modeling. Data Modeling is the process of analyzing and defining different data type that is collected or produced. I learnt that before creating dashboards or visualizations, it’s critical to properly structure and connect your data. Our teacher illustrated the importance of using power query to remove duplicates, handle blanks , filter and sort data and merge and reshape datasets. Joins vs Relationships Joins are used in tools like SQL or Power Query to physically combine tables into one. In Power BI, joins usually happen in Power Query before the data is loaded into the model. Relationships in Power BI link tables without merging them, allowing for more flexible and efficient analysis. we were taught that Power BI prefers relationships over joins because they help maintain clean, scalable data models. SQL join types An inner join returns only the rows that have matchi