A “data warehouse” can take many forms. The most common definition is:
A collection of information gathered together from multiple sources for the purpose of generating reports and analyses.
A data warehouse provides a unique capability to report information that can not be easily generated from the source systems themselves. This can be due to one or more of several factors:
The source system is designed for fast inputs and updates, but is difficult to use for reporting. The data warehouse reformats the data for “write once - read many” performance
The information across several systems is “joined” together to give new insights
The data changes over time, and the data warehouse can provide a time-based view of those changes and trends
A “data warehouse” can take many forms. Over the years, new ways to design and update these reporting structures have been developed. For that reason, we currently are building a new warehouse to take advantage of the latest advances in data warehousing. For more information, See Also: Enterprise vs. Legacy Warehouse article