In Reporting Services, parameters are used to specify the data to use in a report,
connect related reports together, and vary report presentation. To design a report
that uses parameters effectively, you must understand how parameters and dataset
queries work together, how parameters and expressions work together, how parameters
can be managed on the report server for a published report, and what questions a
report is designed to answer. What you choose to parameterize can influence the
report design and layout.
Query parameters are added to a dataset query by way of the query designers or the
Dataset Properties dialog box. After you create a query with parameters, Reporting
Services automatically links query parameters to report parameters with the same
name. New report parameters are added and modified by way of the Report Data pane.
Using Parameters in Reporting Services
The most common use of parameters is to vary report data retrieved by dataset queries.
In this scenario, users are prompted for a value or values when they run the report,
and the dataset query retrieves only the data that is requested. The dataset query
includes query parameters and Reporting Services automatically creates corresponding
report parameters that are indirectly linked to the query parameters. You can change
the report parameter properties in the report design tools to include a valid values
list and a user prompt that displays at run time.
You can also create cascading parameters, which retrieve hierarchical data from
a data source. For example, the first parameter might filter on product category,
and the second parameter might filter on product. Cascading parameters are used
to organize and limit the number of available values for the user.
Not all data sources support queries parameters. For those times when you cannot
filter data at the source, you can use report parameters to provide a users with
the ability to filter data after it has been retrieved for the report. While all
query parameters have corresponding report parameters, you can define report parameters
independently in the report designer tools. Report parameters can also be used to
change the appearance or organization of a report after the data has been retrieved.
Parameters are used to connect reports to sub reports and drillthrough reports.
These report parameters might be hidden, using values in the main report to select
the correct data for the connected report, or they might be visible to the user
at run time.
After a report parameter is created, you can modify the default values and other
parameter properties, such as visibility. For example, report parameters can use
built-in variables like UserID, so you might want to create a report with a hidden
parameter that selects data specific to the user running the report. Parameters
can contain single values or multiple values, use a static or query-based valid
values list, and accept null or blank values. Multivalue parameters enable users
to select more than one value at run time.
After a report is published, parameters can be managed independently from the report
definition. Depending on how you configure the parameter in the report at design
time, report server administrators can modify many parameter properties in the published
report. They can also create sets of parameters linked to the same report definition
that customize the report for multiple audiences.
Parameters in Reporting Services
Using Parameters to Control Report Data Discusses how to use parameters to filter report data, to change the sort order
for detail and group data, and to modify queries to work with specific data providers.
Using Query Parameters with Specific Data Sources (Reporting
Services) Describes the query syntax expected by the various data sources.
Using Parameters to Control Report AppearanceDiscusses how to use parameters to change report appearance using expression-based
properties, including conditionally hiding report items and conditionally changing
text color based on the values of a text box.
Using Parameters to Connect to Other ReportsDiscusses how to use parameters to link to drillthrough reports, subreports, and
linked reports.
Using Single-Value and Multivalue Parameters Discusses how to use single-value and multivalue parameters.
Creating Report Parameters and Setting Report Parameter
Properties Discusses how to create and set properties on a report parameter when you author
the report, including data type, default values, parameter prompts, available values,
multiple values, and whether parameters are internal, hidden, or visible to the
user at run time.
