Introduction to MSSQL Server 2000 Analysis Services: Performing Incremental Cube Updates - An Introduction

About the Series ...

This article is a member of the series Introduction to MSSQL Server 2000 Analysis Services. The series is designed to provide hands-on application of the fundamentals of MS SQL Server 2000 Analysis Services, with each installment progressively adding features and techniques designed to meet specific real - world needs. For more information on the series, as well as the hardware / software requirements to prepare for the exercises we will undertake, please see my initial article, Creating Our First Cube.

Overview

Having processed cubes in preceding articles, we are aware that processing calculates the aggregations that have been designed for the cube, and then loads the cube with the data, and the calculated aggregations of the data. While we have looked only at Full Processing in most of my articles, we will expose other approaches to processing in this session. We will then focus on the use of a tool that MSAS provides to help us to exploit one of those options, the incremental processing of our cubes.

The processing of cubes, once we get beyond the basics, is complex subject matter. Nevertheless, an in-depth grasp of the subject is highly critical to mastering optimization of our cubes and MSAS in general. For this reason, I will be spending considerable time within the articles of this series (as well as articles and columns elsewhere) that address many nuances and approaches to the tuning of the processing event. Our purpose within this article, however, is to overview the Incremental Processing Wizard, and, within that context, the concept of incremental processing.

In this article, we will introduce the MSAS Incremental Processing Wizard, whose role is to enable us to perform incremental updates of our cubes, while helping us to steer clear of some of the dangers that are inherent with incremental processing. We will first discuss processing in general, and then focus on incremental processing as a concept within the context of MSAS cubes. Next, we will perform a hands-on exercise where we incrementally update a copy of one of the sample cubes that accompany the installation of MSAS.

Our objective in this article is an overview of the wizard itself; other of my articles will focus on specific processing strategies and techniques. Within our exploration of the Incremental Update Wizard, we will accomplish the following:

• Create a copy of the Budget sample cube for use in our practice exercise.
• Prepare the cube further by processing.
• Perform a practice exercise, using the Incremental Update Wizard, to incrementally update our practice cube.
• Examine the options that are available to us, as we proceed through the guided steps of the Wizard.
• Confirm our understanding of the mechanics behind the action of the Incremental Update Wizard by examining pre- and post- update values, as a straightforward means of verifying that the difference we compute equals the value we established to be added via the incremental update.