Using MDX with DeepSee
Adding Summaries
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This chapter describes how to add summaries (such as averages and totalsxt) to your MDX queries. It discusses the following topics:

Introduction to Summary Functions
MDX includes functions that summarize a given value, across a given set. For each function, the arguments are a set and an optional numeric expression (such as a reference to a measure). DeepSee evaluates the expression for each member of the set and then returns a single value. If no numeric expression is given, DeepSee instead evaluates the measure used in the query (possibly %COUNT).
The functions are as follows:
For example:
SELECT MAX(diagd.diagnoses.MEMBERS,MEASURES.[%COUNT]) ON 0 FROM demomdx

This query shows the maximum value of the %COUNT measure for the members of the Diagnoses level.
For another example, use the same function without specifying its second argument. In this case, the query displays the %COUNT measure as a column:
SELECT MEASURES.[%COUNT] ON 0, MAX(diagd.diagnoses.MEMBERS) ON 1 FROM demomdx

MAX                                     828
For another example, use the same function without specifying any measure in the query at all:
SELECT MAX(diagd.diagnoses.MEMBERS) ON 0 FROM demomdx

In this case, DeepSee uses %COUNT.
Adding a Summary Line
More typically, rather than displaying the summary value by itself, you include it in a query that shows all the values of the set. This process is analogous to adding a summary line (as a row or column) in a spreadsheet.
The following example shows the %COUNT measure for each diagnosis, followed by the maximum value for this measure across this set:
{diagd.diagnoses.MEMBERS, MAX(diagd.diagnoses.MEMBERS,MEASURES.[%COUNT])} ON 1 FROM demomdx

1 None                                  828
2 asthma                                 90
3 CHD                                    37
4 diabetes                               45
5 osteoporosis                           22
6 MAX                                   828
Notice that the system first computes the %COUNT measure for each member using the aggregation method defined for that measure. In this case, the patients are counted. The asthma member, for example, has a total %COUNT value of 90. The MAX function then obtains the largest value for this measure, across the set of diagnoses.
For another example:
SELECT {gend.gender.MEMBERS, AVG(gend.gender.MEMBERS,MEASURES.[%COUNT])} ON 0, 
                            Female               Male                AVG
%COUNT                          488                512                500
When using the summary functions, you might find it convenient to use named sets, as described in the chapter Working with Sets.” For example, the following query is equivalent to the preceding one:
WITH SET genders AS 'gend.gender.MEMBERS' 
SELECT {genders, AVG(genders,MEASURES.[%COUNT])} ON 0, MEASURES.[%COUNT] ON 1 FROM demomdx
Another way to add a summary line is to define a summary member that combines the displayed members. See “Adding a Summary Member,” in the chapter Creating and Using Calculated Measures and Members.”