An introduction to data warehousing

Before actually getting started, there is an important concept that needs to be covered and that is data warehouse modeling. The data warehouse is a concept that has been around since the 1970s, it is a central database built for reporting that integrates data from disparate sources to a common location and a common schema. It also removes the direct connection between the source systems and the historical data. This means that if you change your source system, you will retain historical records and can decommission the old system.

The schema in a data warehouse in many cases is built in Third normal form (3NF) to ensure that data is only stored once to minimize the storage cost and make it easier to maintain.

Tip

For more information about 3NF, refer to http://en.wikipedia.org/wiki/3NF.

This is a strategy commonly referenced as an Inmon data warehouse coming from the father of data warehousing, Bill Inmon. Also have a look at http://inmoninstitute.com/about...