RDBMS Star Schema

The Star Schema is a popular database schema design used in data warehousing. It is named for its resemblance to a star, where a central fact table is surrounded by dimension tables.

Components of Star Schema

• Fact Table: Contains the quantitative data for analysis, such as sales amounts or quantities. The fact table links to dimension tables through foreign keys.
• Dimension Tables: Store descriptive attributes related to the facts, such as product names, customer details, or dates.

Example of Star Schema

Consider an e-commerce sales data warehouse:

• Fact Table: Sales
• Dimension Tables:
• Product (ProductID, ProductName, Category, Price)
• Customer (CustomerID, CustomerName, Region, AgeGroup)
• Date (DateID, Date, Year, Quarter, Month)
• Store (StoreID, StoreName, Location)

Advantages

• Simplicity: Easy to understand and query.
• Optimized Query Performance: Efficient joins between fact and dimension tables.
• De-normalization: Reduces the number of joins needed for queries.

Disadvantages

• Redundancy: Can lead to increased storage requirements.
• Limited Flexibility: Best suited for simple queries.

© Kevin Luzbetak