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    Question

    Which of the following is a primary advantage of using a

    star schema in a data warehouse design?
    A It reduces data redundancy and enhances data consistency Correct Answer Incorrect Answer
    B It allows for faster querying and better performance in OLAP systems Correct Answer Incorrect Answer
    C It simplifies the ETL process Correct Answer Incorrect Answer
    D It enforces stricter data integrity constraints Correct Answer Incorrect Answer
    E It supports a highly normalized data structure for complex queries Correct Answer Incorrect Answer

    Solution

    The star schema is a popular schema design used in data warehousing because it simplifies complex queries and enhances performance, especially for Online Analytical Processing (OLAP). In a star schema, a central fact table (storing metrics) is surrounded by dimension tables (storing descriptive attributes). The structure is simpler compared to more complex schema designs like snowflake schemas, and the reduced number of joins leads to faster query performance, which is crucial for OLAP systems. This schema enables easy data retrieval because the dimension tables are denormalized, meaning there are fewer joins and faster processing of aggregations and filtering. This efficiency is critical when performing data analysis, as OLAP queries often involve large volumes of data and need to be optimized for speed. The star schema also helps in creating intuitive and easy-to-understand data models for end-users. Why Other Options Are Incorrect:

    • A) While the star schema can reduce complexity, it does not inherently reduce data redundancy. In fact, some redundancy is introduced in the dimension tables since they are denormalized.
    • C) The ETL (Extract, Transform, Load) process can be simplified, but this is not the primary advantage of the star schema. The ETL process often requires significant work for any schema design.
    • D) The star schema does not enforce stricter data integrity constraints. It sacrifices some data integrity in favor of simplicity and performance.
    • E) The star schema is denormalized, meaning it does not support a highly normalized structure. A highly normalized structure is typical of other schema designs, like snowflake schemas.

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