Which of the following is true of three-tier data warehouses?

Correct option is D

In a three-tier data warehouse architecture, data marts are subsets of the data warehouse that are designed for specific business needs. These data marts are updated periodically from the main data warehouse to ensure data consistency and accuracy across the system.
Important Key Points:
1. Three-Tier Architecture: It includes a data source layer, a data warehouse layer, and a user interface layer.
2. Data Marts’ Role: They cater to specific business functions like marketing, finance, or operations.
3. Periodic Updates: Data marts do not pull data directly from operational databases but rely on the data warehouse for periodic updates.
Knowledge Booster:
· Data Marts: A smaller, more focused version of a data warehouse, tailored for specific user groups or purposes.
· Operational Databases vs. Data Warehouse: Operational databases store real-time data, while data warehouses store historical data optimized for analysis.
· Advantages of Data Marts: They improve query performance and reduce data complexity for specific business units.