About the Series …
This is the fifth tutorial article of the
series, MDX in Analysis Services. The series is designed to
provide hands-on application of the fundamentals of MDX from the perspective of
MS SQL Server 2000 Analysis Services ("Analysis Services,");
our primary focus is the manipulation of multidimensional data sources, using
MDX expressions in a variety of scenarios designed to meet real-world business
intelligence needs.
For more information on the series, as well as the hardware /
software requirements to prepare for the tutorials we will undertake, please
see Tutorial 1: MDX Concepts and Navigation.
Note: At the time of writing, Service
Pack 3 updates
are assumed for MSSQL Server 2000, MSSQL Server 2000 Analysis
Services, and the related Books Online and Samples.
Introduction
In our
last tutorial, we exposed the use of
the MDX LookupCube function within Analysis Services, as a means of retrieving
values from multiple cubes simultaneously. We discussed how this offers us
the often-useful option of accessing multiple OLAP data sources together
for analysis and reporting, presenting an example real-world scenario where
this option would be valuable. In addition to exploring the retrieval of data
from multiple cubes, we demonstrated how we could compute a per-unit average,
based upon values retrieved from two separate OLAP data sources, while further
exploring and practicing the use of calculated members as part of the process.
In this lesson, we will explore the use of MDX functions that
incorporate the concept of time into the analysis product that we
wish to create, within the context of expression design. We will practice
adding support for time-based analysis, such as the quantification of change in
values over time, with MDX functions that are ideally suited for that
purpose. Moreover, we will perform exercises to reinforce these concepts
within the context of our OLAP data sources.
In this article, we
will examine the roles that MDX can play in helping us to support the time-based
analysis needs of information consumers, as well as increase our general
knowledge of MDX in Analysis Services, by:
-
Building the concept of time
into our expression designs; -
Incorporating support for
time-based analysis with MDX functions; -
Performing additional practice
with the "from scratch" creation of calculated members -
Handling "divide-by-zero"
scenarios in calculated members; -
Generating variance
calculations.