Which of the following are features of a data warehouse?

A data warehouse is an integrated, subject-oriented, time-variant collection of data that supports decision-making processes. One of the critical features of a data warehouse is data governance. This refers to the overall management of the availability, usability, integrity, and security of the data used in an organization. Effective data governance frameworks ensure that the data within the warehouse is accurate, consistent, and properly managed, which is crucial for reliable reporting and analysis. Proper governance helps organizations maintain compliance with regulations, improve data quality, and enhance the decision-making process by providing users with trusted and validated data.

While the other options, such as real-time reporting, OLTP and OLAP functionalities in one system, and consolidation, may be relevant features in different contexts or scenarios, they do not universally define a traditional data warehouse environment. Data governance, however, stands central to the integrity and reliability of a data warehouse, making it a fundamental feature.