BC remote Oracle DBA - Call (800) 766-1884  
Oracle Consulting Oracle Training Development

Remote DBA

Remote DBA Plans  

Remote DBA Service

Remote DBA RAC

Remote DBA Oracle Home
Remote DBA Oracle Training
Remote DBA SQL Tuning Consulting
Remote DBA Oracle Tuning Consulting
Remote DBA Data Warehouse Consulting
Remote DBA Oracle Project Management
Remote DBA Oracle Security Assessment
Remote DBA Unix Consulting
Burleson Books
Burleson Articles
Burleson Web Courses
Burleson Qualifications
Oracle Links
Remote DBA Oracle Monitoring
Remote DBA Support Benefits
Remote DBA Plans & Prices
Our Automation Strategy
What We Monitor
Oracle Apps Support
Print Our Brochure
Contact Us (e-mail)
Oracle Job Opportunities
Oracle Consulting Prices





Remote DBA services

Remote DBA Support

Remote DBA RAC

Remote DBA Reasons

Remote Oracle Tuning

Remote DBA Links

Oracle DBA Support

Oracle DBA Forum

Oracle Disaster

Oracle Training

Oracle Tuning

Oracle Training

 Remote DBA SQL Server

Remote MSSQL Consulting

Oracle DBA Hosting

Oracle License Negotiation









Oracle Tips 

by Burleson Consulting

The Data Warehouse Development Life Cycle

Data Aggregation And Drill-Down
One of the most fundamental principles of the multidimensional database is the idea of aggregation. As we know, managers at different levels require different levels of summarization to make intelligent decisions. To allow the manager to choose the level of aggregation, most warehouse offerings have a "drill-down" feature, allowing the user to adjust the level of detail, eventually reaching the original transaction data. For obvious performance reasons, the aggregations are pre-calculated and loaded into the warehouse during off-hours. (See Figure 6.2.)

Figure 6.2 Levels of pre-aggregation of summary data.

Of the several types of aggregation, the most common is called a roll-up aggregation. An example of this type of aggregation would be taking daily sales totals and rolling them up into a monthly sales table. These types of summaries are easily computed from the base data warehouse by using the SQL SUM operator.

The more difficult type is the aggregation of boolean and comparative operators. For example, assume that a salesperson table contains a boolean column called turkey. A salesperson is a turkey if his or her individual sales are below the group average for the day. A salesperson may be a turkey on 15 percent of the individual days; however, when the data is rolled up into a monthly summary, a salesperson may become a turkey even if they only had a few (albeit very bad) sales days.

This is an excerpt from "High Performance Data Warehousing". To learn more about Oracle, try "Oracle Tuning: The Definitive Reference", by Donald K. Burleson.  You can buy it direct from the publisher at 30% off here:


Expert Remote DBA

BC is America's oldest and largest Remote DBA Oracle support provider.  Get real Remote DBA experts, call
BC Remote DBA today.



Remote DBA Service

Oracle Tuning Book


Advance SQL Tuning Book 

BC Oracle support

Oracle books by Rampant

Oracle monitoring software







BC Remote Oracle Support

Remote DBA

Remote DBA Services

Copyright © 1996 -  2013 by Burleson. All rights reserved.

Oracle® is the registered trademark of Oracle Corporation.