What is a data warehouse?

What is a data warehouse?

• A. A large data storage facility containing data on major aspects of the enterprise
• B. Combination of many different databases across an enterprise
• C. A collection of operational data sources
• D. A data mart for a single department

Answer: (A)

A data warehouse is a centralized, enterprise-wide repository designed to support business analysis and reporting by integrating data from multiple sources over time. This makes it a large data storage facility containing data on major aspects of the enterprise, organized to be queried for decision support and historical analysis. The idea is to bring together data from various operational systems, clean and transform it, and store it in a single place so analysts can perform cross-functional queries and trend analyses. The other descriptions don’t fit as well: a simple combination of many databases isn’t centralized in a way that supports broad, cross-department analysis; a collection of operational data sources refers to the original source systems rather than a consolidated warehouse; and a data mart serves a single department, which is narrower than an enterprise-wide warehouse.

A data warehouse is a centralized, enterprise-wide repository designed to support business analysis and reporting by integrating data from multiple sources over time. This makes it a large data storage facility containing data on major aspects of the enterprise, organized to be queried for decision support and historical analysis. The idea is to bring together data from various operational systems, clean and transform it, and store it in a single place so analysts can perform cross-functional queries and trend analyses.

The other descriptions don’t fit as well: a simple combination of many databases isn’t centralized in a way that supports broad, cross-department analysis; a collection of operational data sources refers to the original source systems rather than a consolidated warehouse; and a data mart serves a single department, which is narrower than an enterprise-wide warehouse.