Data Warehousing & OLAP Quiz

What is a data warehouse?

• A centralized repository for analysis and reporting

• A system for transaction processing

• A type of operational database

• A tool for real-time data processing

What does OLAP stand for?

• Operational Layer Access Protocol

• Online Analytical Processing

• Online Local Access Protocol

• Organizational Layered Analytical Processing

Which of the following is a characteristic of data warehouses?

• Unstructured data storage

• Real-time data processing

• Subject-oriented organization

• Volatile data storage

What is the purpose of ETL?

• To store data in operational databases

• To analyze data in real-time

• To visualize data for reporting

• To extract, transform, and load data into a warehouse

Which schema design reduces redundancy?

• Snowflake Schema

• Star Schema

• Hybrid Schema

• Flat Schema

What does the roll-up operation do in OLAP?

• Filters data by multiple dimensions

• Rearranges dimensions for analysis

• Accesses detailed data

• Summarizes data to a higher granularity

What is a disadvantage of the Snowflake Schema?

• Increases data redundancy

• Simplifies query performance

• Decreases query complexity

• Requires more storage due to normalization

Which of the following is NOT a step in the ETL process?

• Analyze

• Load

• Extract

• Transform

What is the main focus of data warehouses compared to operational databases?

• Real-time transaction processing

• Aggregated data queries for reporting

• Daily transaction updates

• Storing unstructured data

What does the 'slice' operation do in OLAP?

• Rearranges dimensions

• Summarizes data

• Filters data by one dimension

• Accesses detailed data