Power BI Data Modeling: Fact Tables, Dimension Tables, and Schema Explained

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Power BI data modeling relies on two core table types: fact tables, which store large volumes of numeric and categorical data, and dimension tables, which provide descriptive context at the edges of a schema. A star schema organizes one central fact table surrounded by multiple dimension tables, while a snowflake schema extends this by further normalizing dimension tables into related sub-tables. Relationships between tables are established using primary keys, which uniquely identify each row in a dimension table, and foreign keys, which link those rows back to the fact table. Cardinality defines how rows in one table correspond to rows in another, with the main types being one-to-many, one-to-one, and many-to-many relationships.

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