DATA WAREHOUSING FUNDAMENTALS: A Comprehensive Guide for IT Professionals

15.3. MAJOR FEATURES AND FUNCTIONS

Very often, you are faced with the question of whether OLAP is not just data warehousing in a nice wrapper? Can you not consider online analytical processing as just an information delivery technique and nothing more? Is it not another layer in the data warehouse, providing interface between the data and the users? In some sense, OLAP is an information delivery system for the data warehouse. But OLAP is much more than that. A data warehouse stores data and provides simpler access to the data. An OLAP system complements the data warehouse by lifting the information delivery capabilities to new heights.

15.3.1. General Features

In this section, we will pay special attention to a few major features and functions of OLAP systems. You will gain greater insight into dimensional analysis, find deeper meanings about the necessity for drill-downs and roll-ups during analysis sessions and gain greater appreciation for the role of slicing and dicing operations in analysis. Before getting into greater details about these, let us recapitulate the general features of OLAP. Please go to Figure 15-4 and note the summary. Also note the distinction between basic features and advanced features. The list shown in the figure includes the general features you observe in practice in most OLAP environments. Please use the list as a quick checklist of features your project team must consider for your OLAP system.

15.3.2. Dimensional Analysis

By this time, you are perhaps ...