Question 1

A data warehouse needs to support scalability, which pertains to the amount of data in the warehouse, how quickly the warehouse is expected to grow, the number of concurrent users, and the complexity of user queries.

Accepted Answer

Scalability is an important feature of data warehouses as they are designed to handle large amounts of data and support multiple users with complex query requirements. The ability to scale up or out, meaning increasing the capacity of the system either vertically or horizontally, is crucial to ensure that the data warehouse can meet the demands of growing businesses and changing user needs.

Question 2

The data for an oper mart come from an ODS.

Accepted Answer

The data for an operational data store (ODS) is typically used as the source of data for an operational data mart. The ODS is designed to provide a current, stable, and integrated view of operational data from various sources across an organization, which makes it an ideal source for populating a data mart that focuses on supporting operational reporting and analysis needs.

Question 3

Because of performance and data quality issues, most experts agree that federated approaches work well to replace data warehouses.

Accepted Answer

Federated approaches are not typically used to replace data warehouses, but rather to complement them by allowing for access to data from multiple sources without physically integrating the data into a centralized warehouse. While federated approaches can improve data accessibility and reduce duplication, they can also introduce a host of other challenges, such as security and governance issues, and may not be suitable for all organizations or use cases. Therefore, most experts do not advocate for replacing data warehouses with federated approaches, but rather for using them in combination to optimize data management and analytics.

Question 4

There are many metaware tools that business users can use to access data stored in the data repositories, including data mining, reporting tools, and data visualization.

Accepted Answer

The answer of There are many metaware tools that business...

Question 5

Effectiveness, extensibility, reusability, interoperability, efficiency and performance, evolution, entitlement, flexibility, segregation, user interface, versioning, versatility, and low maintenance cost are some of the key requirements for building a successful metadata-driven enterprise.

Accepted Answer

These are indeed some key requirements for building a successful metadata-driven enterprise.

Question 6

A real-time data warehouse together with a decision support system that leverages integrated data can provide significant financial benefits for an organization.

Accepted Answer

A real-time data warehouse and decision support system can allow for faster and more accurate decision making, leading to cost savings and increased revenue.

Question 7

According to conventional wisdom, independent data marts are a poor architectural solution.

Accepted Answer

Independent data marts can lead to data inconsistency, redundant data storage, and difficulty in sharing data across different departments or functions. A centralized data warehouse is often considered a better architectural solution.

Question 8

Before implementing an active data warehouse solution, DirecTV pulled data from the server every night in batch mode, a process that was taking too long and straining the system.

Accepted Answer

The statement indicates that the process of pulling data from the server every night in batch mode was taking too long and straining the system, leading to the need for an active data warehouse solution.

Question 9

An independent data mart is a small warehouse designed for a strategic business unit (SBU) or a department whose source is an EDW.

Accepted Answer

An independent data mart is designed for a specific department or business unit but it sources its data directly from internal or external data sources, not from an Enterprise Data Warehouse (EDW).

Question 10

ETL tools transport data between sources and targets, document how data elements change as they move between source and target, exchange metadata with other applications, and administer all runtime processes and operations.

Accepted Answer

ETL tools are designed to perform all these tasks.

Question 11

In a three-tier architecture, operational systems contain the data and the software for data acquisition in the first tier, the data warehouse is a second tier, and the third tier includes the DSS/BI/BA engine.

Accepted Answer

This is a correct statement about the three-tier architecture. The first tier contains operational systems, the second tier contains the data warehouse, and the third tier includes the DSS/BI/BA engine.

Question 12

There are several levels of metadata management maturity that describe where an organization is in terms of how and how well it uses its metadata.

Accepted Answer

This statement is true, as there are indeed different levels of metadata management maturity that organizations can be categorized into based on their use and management of metadata.

Question 13

A data warehouse maintains historical data that do not necessarily provide current status, except in real-time systems.

Accepted Answer

A data warehouse is designed to store historical data, typically for analysis and reporting purposes. It is not optimized to provide real-time status updates, which are better suited for transactional or operational systems.

Question 14

Operational data store is used for the medium- and long-term decisions associated with the enterprise data warehouse (EDW).

Accepted Answer

An operational data store is used for short-term operational decisions, while the enterprise data warehouse is used for medium- and long-term strategic decisions.

Question 15

The centralized data warehouse helps to simplify data management and administration and reduce data redundancy.

Accepted Answer

The answer of The centralized data warehouse helps to simplify...

Question 16

A data warehouse differs from an operational database in that most data warehouses have a product orientation and are designed to handle transactions that update the database.

Accepted Answer

A data warehouse has a subject orientation, meaning it is designed to store historical data for analysis and decision-making purposes. It is not designed for real-time transaction processing like an operational database.

Question 17

Once the data are entered into the data warehouse, users cannot change or update the data.

Accepted Answer

Once data is loaded into a data warehouse, it is considered as read-only and cannot be changed or updated by users. The purpose of a data warehouse is to store historical data for analysis and decision-making, and allowing users to update data could compromise its integrity and reliability.

Question 18

There are three main types of data warehouses, which are data marts, operational data stores, and enterprise data warehouses.

Accepted Answer

This statement is true. There are three main types of data warehouses: data marts, operational data stores, and enterprise data warehouses.

Question 19

There are ethical considerations involved in the collection and ownership of the information contained in
metadata, including privacy and intellectual property issues.

Accepted Answer

Metadata can reveal personal information about individuals such as their location, browsing habits, and interests. As such, the collection and ownership of this information should be done responsibly and with consideration for privacy and intellectual property rights. Failure to do so could result in legal consequences and damage to a company's reputation.

Question 20

A hosted data warehouse has less functionality than an onsite data warehouse, but it does not consume computer resources on client premises for computer upgrades, software licenses, in-house development, and in-house support and maintenance.

Accepted Answer

A hosted data warehouse can offer comparable functionality to an onsite data warehouse, and its main advantage is indeed that it does not consume resources on client premises for upgrades, licenses, development, and support.

Quiz 2: Data Warehousing