Practice Library
All MCQs
Browse exam-wise, subject-wise, and country-wise MCQs with explanations.
Choose an option to check your answer.
A.
Warehouses usually load data in controlled batches or streams rather than through user transactions
B.
Warehouses update every row whenever a user opens a report
C.
OLTP systems never insert data
D.
OLTP systems store only yearly summaries
Show Answer
Correct Answer: A. Warehouses usually load data in controlled batches or streams rather than through user transactions
Explanation:
Warehouse changes are generally introduced through managed integration processes.
Choose an option to check your answer.
A.
Warehouse tables have no dependencies
B.
Schema changes affect only chart colors
C.
Operational users automatically rewrite ETL code
D.
Historical loads, ETL mappings, semantic models, and reports can all depend on the schema
Show Answer
Correct Answer: D. Historical loads, ETL mappings, semantic models, and reports can all depend on the schema
Explanation:
A warehouse sits within a chain from sources to reports.
Choose an option to check your answer.
A.
A transaction log record
B.
A source-system input form
C.
An OLAP structure or warehouse aggregate
D.
A network routing table
Show Answer
Correct Answer: C. An OLAP structure or warehouse aggregate
Explanation:
Aggregates accelerate repeated analytical queries over common groupings.
Choose an option to check your answer.
A.
A monthly warehouse snapshot
B.
The operational order-processing system
C.
A historical cube processed last night
D.
An archived dashboard image
Show Answer
Correct Answer: B. The operational order-processing system
Explanation:
Operational systems maintain the latest transaction state.
Choose an option to check your answer.
A.
Large sequential reads and aggregation of many rows
B.
Constant updates to the same small set of rows
C.
One-row inserts with no analytical queries
D.
Exclusive locks held for long user sessions
Show Answer
Correct Answer: A. Large sequential reads and aggregation of many rows
Explanation:
Analytical queries often scan and aggregate broad sections of fact data.
Choose an option to check your answer.
A.
Only one analyst may view a cube at a time
B.
Historical data must never be queried
C.
All tables are loaded only once per year
D.
Many users may execute simultaneous transactions on operational data
Show Answer
Correct Answer: D. Many users may execute simultaneous transactions on operational data
Explanation:
Operational systems often serve many simultaneous customers and employees.
Choose an option to check your answer.
A.
Insert one new payment record
B.
Change one customer’s shipping address
C.
Compare quarterly profit by region for the last six years
D.
Cancel a single pending order
Show Answer
Correct Answer: C. Compare quarterly profit by region for the last six years
Explanation:
OLAP queries analyze substantial historical data across dimensions.
Choose an option to check your answer.
A.
Scanning five years of sales by region
B.
Updating the status of one customer order
C.
Calculating annual market share across all products
D.
Building a cube aggregation design
Show Answer
Correct Answer: B. Updating the status of one customer order
Explanation:
OLTP transactions are typically short, focused, and affect few rows.
Choose an option to check your answer.
A.
To simplify analytical queries and reduce joins
B.
To increase update anomalies intentionally
C.
To enforce row-by-row transaction locking
D.
To prevent users from aggregating measures
Show Answer
Correct Answer: A. To simplify analytical queries and reduce joins
Explanation:
Denormalized dimensions make business attributes easier to query.
Choose an option to check your answer.
A.
To maximize repeated descriptive values
B.
To eliminate all table joins
C.
To precompute every possible aggregate
D.
To reduce redundancy and update anomalies during transactions
Show Answer
Correct Answer: D. To reduce redundancy and update anomalies during transactions
Explanation:
Normalization keeps transactional updates consistent and avoids unnecessary duplication.
Choose an option to check your answer.
A.
Capture each point-of-sale transaction
B.
Maintain source-code versions
C.
Enable multidimensional analysis of aggregated and historical data
D.
Manage network authentication logs
Show Answer
Correct Answer: C. Enable multidimensional analysis of aggregated and historical data
Explanation:
OLAP supports interactive analysis across dimensions and levels of detail.
Choose an option to check your answer.
A.
Store only summarized historical measures
B.
Process routine business transactions accurately and efficiently
C.
Support multidimensional trend analysis
D.
Create executive dashboards from cubes
Show Answer
Correct Answer: B. Process routine business transactions accurately and efficiently
Explanation:
OLTP systems record day-to-day events such as orders and payments.
