1. Who introduced the concept of “Business Data Warehouse”?
A) Bill Inmon
B) Barry Devlin and Paul Murphy
C) Ralph Kimball
D) E.F. Codd
Answer: B
2. The main goal of data warehousing is to:
A) Process transactions
B) Maintain historical information and support decision-making
C) Store raw operational data only
D) Replace operational databases
Answer: B
3. Which of the following is NOT a need for a data warehouse?
A) Store historical data
B) Make strategic decisions
C) Improve OLTP speed
D) Ensure data consistency
Answer: C
4. Which component of a data warehouse is responsible for preparing data before storage?
A) Source Data Component
B) Data Staging Component
C) Data Storage Component
D) Metadata Component
Answer: B
5. The process of correcting misspellings and removing duplicates is part of:
A) Data Extraction
B) Data Transformation
C) Data Loading
D) Data Querying
Answer: B
6. Initial loading of the data warehouse happens:
A) Daily
B) Weekly
C) Only once when going live
D) Every time a query is run
Answer: C
7. Which component stores “data about data” in a warehouse?
A) Metadata Component
B) Data Storage Component
C) Data Marts
D) Management Component
Answer: A
8. A subset of a corporate data warehouse designed for a specific group is called:
A) Data Cube
B) Data Mart
C) OLTP System
D) Metadata Repository
Answer: B
9. In the three-tier architecture, OLAP servers are part of the:
A) Top Tier
B) Middle Tier
C) Bottom Tier
D) External Tier
Answer: B
10. Which OLAP model works only with relational databases?
A) ROLAP
B) MOLAP
C) HOLAP
D) DOLAP
Answer: A
11. Which OLAP model is a combination of relational and multidimensional systems?
A) ROLAP
B) MOLAP
C) HOLAP
D) SOLAP
Answer: C
12. In a star schema, dimension tables are:
A) Normalized
B) Denormalized
C) Indexed only
D) Empty
Answer: B
13. Which schema allows sub-dimension tables connected to dimension tables?
A) Star
B) Snowflake
C) Galaxy
D) Hybrid
Answer: B
14. Which schema has multiple fact tables sharing dimensions?
A) Star
B) Snowflake
C) Galaxy (Fact Constellation)
D) Hybrid Schema
Answer: C
15. Which schema design generally requires more disk space due to redundancy?
A) Star Schema
B) Snowflake Schema
C) Galaxy Schema
D) Fact Table Schema
Answer: A
16. Which step in ETL includes combining data from multiple sources?
A) Extraction
B) Transformation
C) Loading
D) Archiving
Answer: B
17. Which is NOT a benefit of Snowflake Schema?
A) Less storage space
B) No data redundancy
C) Easy updates
D) Faster queries than star schema
Answer: D
18. The multi-dimensional data model organizes data as:
A) Linked lists
B) Data cubes
C) XML files
D) Entity-Relationship diagrams
Answer: B
19. The fact table in a star schema contains:
A) Descriptive attributes only
B) Numerical measures (facts) and foreign keys to dimensions
C) Metadata only
D) OLAP server logs
Answer: B
20. The OLAP operation that aggregates data by climbing up a hierarchy is:
A) Drill-down
B) Slice
C) Roll-up
D) Pivot
Answer: C
21. The OLAP operation that adds detail by going to lower levels in a hierarchy is:
A) Roll-up
B) Drill-down
C) Slice
D) Dice
Answer: B
22. The OLAP operation that selects one particular dimension value is:
A) Roll-up
B) Slice
C) Dice
D) Pivot
Answer: B
23. The OLAP operation that selects multiple dimensions is:
A) Dice
B) Slice
C) Roll-up
D) Drill-down
Answer: A
24. Pivot operation in OLAP is also known as:
A) Rotation
B) Filtering
C) Aggregation
D) Joining
Answer: A
25. Which of the following is TRUE about OLTP systems?
A) They store historical data
B) They handle day-to-day transactions
C) They are used mainly for analysis
D) They are based on multidimensional models
Answer: B
26. OLAP systems are mainly used by:
A) Clerks
B) Database Administrators
C) Managers and Analysts
D) Cashiers
Answer: C
27. Which OLAP type works entirely on multidimensional databases?
A) ROLAP
B) MOLAP
C) HOLAP
D) WOLAP
Answer: B
28. In OLAP vs OLTP, OLAP focuses on:
A) Data in
B) Information out
C) Transaction speed
D) Real-time updates
Answer: B
29. In the three-tier architecture, which tier contains ETL processes?
A) Top Tier
B) Middle Tier
C) Bottom Tier
D) Client Tier
Answer: C
30. Which concept defines mapping from low-level to high-level concepts in dimensions?
A) Data Cube
B) Concept Hierarchy
C) Metadata
D) Data Mart
Answer: B
