| MDX Introduction and Overview |
MDX extracts multidimensional
views of data. A tuple is a slice of data from a cube. It is
a selection of members (or cells) across dimensions in a cube. It can also
be viewed as a cross-section or vector of member data in a cube. A tuple can
be composed of member(s) from one or more dimensions. However, a tuple cannot
be composed of more than one member from the same dimension.
Sets are collections
of tuples. The order of tuples in a set is important when querying cube data
and is known as dimensionality. It is important to note
that the order of the dimension members in every tuple must be the same.
For example, if your first tuple is (time_dimension_member, geography_dimension_member),
then every other tuple in that set must also have two members in it, the first
from the time dimension and the second from the geography dimension.
Copyright © 2009 by SAS Institute Inc., Cary, NC, USA. All rights reserved.
