Kimball University: Four Fixes Refurbish Legacy Data Warehouses

DW/BI professionals are often tasked with making evolutionary upgrades and improvements to minimize cost and upheaval in the current analytic environment. We explore four upgrades that can breathe new life into legacy data warehouses.

Face The Realities

We've described four of the most common data fixes for more mature warehouses. It's worth noting that regardless of the opportunities for improvement with your existing environment, it's important to evaluate the costs versus benefits of taking any corrective action. It's similar to the decision process when confronted with maintenance of an aging automobile; sometimes it makes sense to spend the money, but other times you may opt to merely live with the dents or dump the heap of junk altogether.

Keep your eyes open for occasions when the impact of the corrective action is either less noticeable or less painful. For example, if your organization is implementing a new operational source system or migrating to a new ETL or BI tool platform, the upheaval with your existing transformation and/or analytic processes presents an opportunity for other corrections. Using the automobile maintenance analogy, if your car is already in the shop and the mechanic has lifted the hood to change the oil, he might as well check the windshield wiper fluid while he's in there.

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Margy Ross is president of The Kimball Group. She has focused on DW/BI consulting and education since 1984. Write to her at [email protected].

Required Reading:

The Matrix: Revisited
Data Stewardship 101
Integration for Real People
Integration for Real People
The Data Warehouse Toolkit, 2nd Edition by R. Kimball and M. Ross(John Wiley & Sons, 2002)