Pro SQL Server 2012 Reporting Services

CHAPTER 6  BUILDING REPORTS

threshold that you will set will be for the average number of visits per day. The method to derive this

value is a simple calculation of a distinct count of the unique field Trx.ServicesTblID divided by a range

of days, say 365 for a year. Our calculation for the Pro_SSRS database reveals an average of 44 daily visits

for 2009. The next step, then, is to create a report variable that will hold this threshold value.

To set up a report variable, open up the EmployeeServiceCost_Variables_Start.rdl report from the

Pro_SSRS project and go to the Design tab, click Report Properties under the Report menu, and click the

Variables tab. Click Add and enter Threshold as the name of the variable, 44 as the value, and remove

the check from Read-Only, as shown in Figure 6-39.

Figure 6-39. Adding a report variable

Like report variables, group variables can be configured for one or more row or column groups.

They are useful for storing static values, such as differing tax values for products and product

subcategories, or subgroups.