Explain the difference between star schema and snowflake schema

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Accepted Answer

Star schema has a single fact table connected to multiple dimension tables, while snowflake schema has normalized dimension tables.

Star schema denormalizes data for faster query performance.
Snowflake schema normalizes data to reduce redundancy and improve data integrity.
Star schema is easier to understand and query, but snowflake schema is more flexible and scalable.
Example: A star schema for a sales database would have a fact table for sales transactions connected to dimension tables for products, customers, and time.
Example: A snowflake schema for the same sales database would have separate normalized dimension tables for product categories, subcategories, and products.

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