Advanced Cube Design - Professional SQL Server Analysis Services 2005 with MDX - page 433

Figure 9-41
3. Click Sales Reason Comparions for Bikes. A browser window will
open. If Reporting Services 2005 is installed, you will see a mes-
sage, The item '/AdventureWorks Sample Reports/Sales Reason
Comparisons' cannot be found; in other words, rsItemNotFound. This
is because the report is fictitious. Were it a valid report, the report
would display the sales reasons for the Bike category.
Drill-Through Action
OLAP is all about aggregating data and serving aggregating data to end
users quickly. Users want to analyze data hierarchically by drilling up and
drilling down which requires aggregated data from millions of daily transaction
rows. Sometimes it is very useful for users to be able to retrieve the transac-
tion rows that have been aggregated into a particular cell. Access to such de-
tails often helps business users understand any abnormal business activities
(such as extremely large or small numbers) and investigate root causes. Drill-
through provides this access to details by enabling users to fetch the fact
table rows that contribute to an aggregation value of a cube cell.
Drill-through in Analysis Services 2000 is a special MDX command which is
also supported in Analysis Services 2005. However in Analysis Services 2005
you can also create a special action type called Drillthrough. A Drillthrough
action's target is always one or more cube cells associated with a specific
measure group. In other words, cells with measures in the target measure
group will display the available drill-through actions on the pop-up menu. Drill-
through actions return the related fact table rows in a tabular rowset. As the
action developer, you specify which columns the action returns. The columns
in the return rowset when a drill through action is executed are not limited to
the actual fact table columns. Any dimension attributes linked to the selected