ACC 360 Study Guide - Database Server, Online Analytical Processing, Application Server
Document Summary
Wherever possible, normalized tables pertaining to selected events should be consolidated into denormalized tables. Because of the vast size of a data warehouse, inefficiency caused by joining normalized data can be very detrimental to the performance of the system. A three-way join between tables in a large data warehouse may take an unacceptably long time to complete and may be unnecessary. Olap servers support common analytical operations including consolidation, drill down, and slicing and dicing: consolidation is the aggregation or roll-up of data. For example, sales offices data can be rolled up to districts and districts rolled up into regions: drill-down permits disaggregating data to reveal the underlying details that explain certain phenomena. For example, the user can drill down from total sales returns for a period to identify the actual products returned and the reasons for their return: slicing and dicing enables the user to examine data from different viewpoints.
