Warehouse Schemas Dimension values are usually encoded using small integers and mapped to full values via dimension tables Resultant schema is called a star schema More complicated schema structures Snowflake schema:multiple levels of dimension tables Constellation:multiple fact tables Database System Concepts-6th Edition 20.9 ©Silberschat乜，Korth and SudarshanDatabase System Concepts - 6 20.9 ©Silberschatz, Korth and Sudarshan th Edition Warehouse Schemas Dimension values are usually encoded using small integers and mapped to full values via dimension tables Resultant schema is called a star schema More complicated schema structures  Snowflake schema: multiple levels of dimension tables  Constellation: multiple fact tables