Data Warehouse Ongoing Maintenance Oracle Tips by Burleson Consulting

The Data Warehouse Development Life Cycle

Data Warehouse Development Methods  

Phase 5: Ongoing Maintenance

Ongoing maintenance is the final phase of the creation of a warehouse. The ongoing maintenance of the warehouse generally involves the constant loading of new data and addressing the changing analysis requirements of end-users.

If a development team has done a good job of analyzing, designing, and coding a new system, you might suspect that the programming team would disband immediately after coding is completed. But, this is not the case. In Figure 2.1, you can see that the cost curve continues to grow after a system has been delivered. This can be attributed to the dynamic nature of systems requirements. Almost by definition, most long-term development efforts will deliver an obsolete system to their end-users. The end-users often lament, “You gave me the system that I needed two years ago when you began the project! Many requirements have changed, even while you were creating the system.” Of course, this is a very common complaint, and it is not surprising to see that the programming staff immediately begins addressing the maintenance requests that have been stacking up while they were initially creating the system. Of course, a traditional computer system will continually become more and more expensive to maintain, until the cumulative costs exceed the benefits of the system. A goal of a savvy systems manager is to foresee this dilemma and to start rewriting the system so that a new system is ready to replace the aging system when the costs become too cumbersome.

Here, you will begin to see some of the major differences between a warehouse project and the type of project that you may have worked on in the past. As noted earlier, systems analysis and design phases are very data-centric as opposed to process-centric. In the early stages of warehouse development, designers are very concerned about collecting all of the data from the legacy data feeds and not at all concerned with how end-users may use the data.

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This is an excerpt from "High Performance Data Warehousing", copyright 1997.

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