WorksheetsData Warehouse Intro and Architecture
Total questions: 30
Worksheet time: 10mins
What is the primary purpose of a data warehouse?
To store transactional data
To analyze and report historical data
To replace operational databases
To store user credentials
Which characteristic is NOT a feature of a data warehouse?
Integrated
Subject-oriented
Volatile
Time-variant
In OLTP systems, the focus is primarily on:
Data analysis
Transaction processing
Archiving data
Generating random queries
Which system is optimized for fast query performance over large datasets?
OLAP
OLTP
ERP
CRM
What is a star schema?
A database design for operational systems
A schema with multiple fact tables
A simple design with one fact table and multiple dimension tables
A schema shaped like a galaxy
Which of the following is a key component of a data warehouse architecture?
ETL process
OLTP systems
Web servers
Machine learning models
True or False: Data in a data warehouse is updated frequently like in OLTP systems.
TRUE
FALSE
What is a dimension in the context of data warehousing?
A table containing numeric data
A table used for storing descriptive data
A table storing historical logs
A table that exists in another dimension
What is the role of ETL in data warehousing?
Export, Transfer, Link
Execute, Test, Log
Eat, Train, Learn
Extract, Transform, Load
True or False: OLAP tools are used for detailed transaction processing.
TRUE
FALSE
Which of the following best describes "time-variant" data in a data warehouse?
Data that changes frequently
Data stored with a historical perspective
Data stored in multiple time zones
Data that is time-sensitive
What is a fact table?
A table that stores transactional data
A table that contains metrics and measures
A table that stores only textual data
A table that provides fun facts about data
True or False: Star schemas are more complex than snowflake schemas.
TRUE
FALSE
What is the main difference between OLAP and OLTP systems?
OLAP systems are more volatile than OLTP systems
OLAP is designed for analytical queries, OLTP is designed for daily operations
OLAP is for transaction processing, OLTP is for data analysis
OLAP systems require less storage than OLTP systems
What does the term "data mart" refer to?
A tool for data visualization
A smaller version of a data warehouse focused on a specific subject
A method for data encryption
A type of database used for operational processing
True or False: Data warehouses are designed for real-time data processing.
FALSE
TRUE
Which of the following best describes a snowflake schema?
A design that is optimized for OLTP systems
A schema that uses only one table
A simple design with one fact table and no dimensions
A complex design with normalized dimension tables
Which of the following is an example of a dimension in a data warehouse?
Sales Transaction ID
Product Category
Total Revenue
Order Amount
What is an advantage of OLAP systems over OLTP systems?
OLAP systems process transactions faster
OLAP systems provide complex analytical queries and reporting
OLAP systems replace operational databases
OLAP systems do not store historical data
A retail company wants to analyze customer purchases over time. Which of the following would most likely be stored in the fact table?
Customer Name
Product Price
Date of Birth
Product Category
A supermarket chain uses a data warehouse to analyze sales trends. Which dimension would help them compare sales across different locations?
Transaction Amount
Store Location
Profit Margin
Total Revenue
An airline wants to analyze flight delays. Which is a dimension?
Delay Time
Flight Number
Ticket Price
Passenger Count
A company tracks daily sales. What should be in the fact table?
Product Name
Category
Sales Amount
Supplier Name
Shopee wants a schema where dimension tables are normalized to avoid redundancy. What schema should they use?
Star Schema
Snowflake Schema
Hybrid Schema
Pyramid Scheme
Pertamina needs to analyze fuel sales across gas stations. What schema is the simplest for reporting and performance?
Snowflake Schema
OLTP Schema
Roll-up Schema
Star Schema
McDonald's wants to analyze customer order patterns. Which is a good dimension for their data warehouse?
Order Total
Order Date
Order ID
Ketchup Quantity
Gopay wants to integrate transaction data from ride payments, merchant payments, and QR scans. What should they do?
Store everything in a single table
Perform Data Integration in a Data Warehouse
Manually input data from each source
Just hope it works
Uniqlo wants to generate monthly sales reports. Which ETL process step ensures product names are consistent across sources?
Extract
Transform
Copy-Paste
Load
Grab wants to analyze driver performance over months. What type of table should store trip distance, rating, and earnings?
Fact Table
TikTok Comments Section
Dimension Table
Staging Table
What is the main function of the 'Load' step in the ETL process?
To delete outdated data
To load data into the data warehouse
To transform data into a suitable format
To extract data from source systems
