Power BI Data Modelling: Fact Tables, Relationships, and Schema Explained

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Power BI enables organizations to convert raw data into actionable insights, but accurate analysis depends on a well-structured data model. Data modelling involves organizing data from multiple sources into related tables using keys, rather than storing everything in a single flat table. Three common structural approaches exist: flat tables, star schemas, and snowflake schemas, each with distinct trade-offs in complexity, performance, and scalability. A star schema, which connects a central fact table to surrounding dimension tables, is generally recommended for Power BI due to its efficiency and ease of DAX calculation. Understanding relationships, filter propagation, and Power Query joins is essential for building reliable and maintainable Power BI reports.

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