Triaging source data

Triaging source data

One of the most difficult things to do in data warehousing is to engage a new source system. Learning about the fields the system has to offer the data warehouse, when they are populated, how "clean" the fields are and when you can get after them with your extract job can be daunting. Then, after going through the process of attaching the extract jobs, scheduling and beginning the cycles, you would want to be set for a while.

Not so fast. Usually 1 day to 2 weeks after putting a data warehouse – any iteration – into production (or prototype) -, users who previously communicated requirements in abstract terms are now seeing the results and requiring changes. New fields and new transformations are not unheard of at this point.

Although data warehousing is very dynamic, it is possible for a practitioner to think beyond initial, spoken requirements and "prime the pump" by bringing additional fields into the ETL process. This concept, known as "triage" works very well if you have a staging area where initial loading from source is "dropped" prior to the majority of the transformations.

With triage and a staging area, the staging area can contain many more fields than are moved forward to the actual data warehouse. Then, if a new field is needed in the warehouse, there is no effect on the source extracts (and no accompanying disruption of source operation and negotiation with the source system team).

But wait, you say. What about

    Requires Free Membership to View

    When you register, you'll begin receiving targeted emails from my team of award-winning editorial writers on the latest customer relationship management (CRM)and call center technology issues today. Our goal is to keep you informed on the hottest issues facing this fast-changing industry.

    Hannah Smalltree, Editorial Director

    By submitting your registration information to SearchCRM.com you agree to receive email communications from TechTarget and TechTarget partners. We encourage you to read our Privacy Policy which contains important disclosures about how we collect and use your registration and other information. If you reside outside of the United States, by submitting this registration information you consent to having your personal data transferred to and processed in the United States. Your use of SearchCRM.com is governed by our Terms of Use. You may contact us at webmaster@TechTarget.com.

the historical data that usually accompanies such new data sourcing? In tomorrow's tip, we'll address that…

For more information, check out SearchCRM's Best Web Links on Data Warehousing.

To ask William a question about this strategy, simply visit our Ask the Expert section in the  Business Intelligence category.


This was first published in July 2002

Join the conversationComment

Share
Comments

    Results

    Contribute to the conversation

    All fields are required. Comments will appear at the bottom of the article.

    Disclaimer: Our Tips Exchange is a forum for you to share technical advice and expertise with your peers and to learn from other enterprise IT professionals. TechTarget provides the infrastructure to facilitate this sharing of information. However, we cannot guarantee the accuracy or validity of the material submitted. You agree that your use of the Ask The Expert services and your reliance on any questions, answers, information or other materials received through this Web site is at your own risk.