About the Series …
This is the fourteenth article of the series, MDX
Essentials. The series is designed to provide hands-on application of the
fundamentals of the Multidimensional Expressions (MDX) language, with
each tutorial progressively adding features designed to meet specific
real-world needs.
For more information about the series in general, as well as
the software and systems requirements needed for getting the most out of the
lessons included, please see the first article, MDX at
First Glance: Introduction to MDX Essentials.
Note: Service Pack 3 updates are assumed for MSSQL
Server 2000, MSSQL Server 2000 Analysis Services, and the related Books
Online and Samples.
What We Accomplished in our Last Article
In the
last article of the series, Basic
Set Functions: The Union() Function, we explored
the commonly used Union() function, whose purpose is to
combine two sets into one. We discussed the function in general, along with the
capabilities it affords us within MDX, emphasizing its value within our
analysis toolsets.
In addition to discussing the purpose and operation of the Union()
function, we examined both primary and alternate syntaxes involved in its use,
illustrating the application of each in practice exercises. Focusing on the
treatment of duplicates in each of the syntactical approaches, we discussed the
results we obtained in each exercise, remarking on distinguishing
characteristics of each.
Introduction
In
this lesson, we will focus our attention on a function that has some
characteristics in common with the Union()
function, yet produces a very different result. The rather simple purpose of
the Intersect() function is to compare two sets, then to return a set
that consists of members that exist in both original sets; that is, to return
a mathematical set intersection of the sets specified in the function.
Indirect uses of Intersect() are quite common, as well. Like the Union() function, the Intersect()
function provides important capabilities within MDX, and is a valuable part of
our analysis toolsets
Along
with an introduction to the Intersect() function, this lesson will
include:
- an examination of the syntax surrounding the function;
-
illustrative examples of the uses of the function in practice
exercises; -
a brief discussion of the MDX results we obtain in the practice
examples.
