What is the primary difference between a Star Schema and a Snowflake Schema?
Star Schemas are used for real-time analytics.
Snowflake Schemas normalize dimension tables.
Snowflake Schemas don't use fact tables.
Star Schemas have more joins.
Why is data redundancy undesirable in a database?
It complicates data retrieval and manipulation
It increases storage space requirements
All of the above
It can lead to data inconsistencies and anomalies
In a Star Schema, what is the central table called that contains the key performance indicators (KPIs)?
Lookup Table
Entity Table
Fact Table
Dimension Table
Which of the following is NOT a valid action for cascading actions in SQL?
ON INSERT CASCADE
ON UPDATE CASCADE
ON SELECT CASCADE
ON DELETE CASCADE
Why is defining a clear and well-structured schema important in database design?
It automates the process of data entry.
It simplifies data management, improves data integrity, and enhances query efficiency.
It eliminates the need for using SQL queries.
It makes the database look visually appealing.
In which scenario might a Snowflake Schema be preferred over a Star Schema?
When dealing with small datasets
When storage space is a major concern
When query performance is the top priority
When data integrity is critical, and redundancy needs to be minimized
Which data validation technique prevents invalid data from being entered into the database by checking it against predefined rules?
Data Masking
Data Scrubbing
Data Transformation
Check Constraints
Which SQL statement is used to create a new table in a database?
NEW TABLE
INSERT TABLE
MAKE TABLE
CREATE TABLE
In which scenario might denormalization be considered acceptable in database design?
To increase data redundancy
To simplify the database schema
To enforce strict data integrity
To improve query performance by reducing joins
Which of the following is a key benefit of using a well-designed schema for a data warehouse?
Improved query performance and efficiency
Simplified data loading from various sources
Reduced need for data modeling and analysis
Increased data redundancy for backups