Built-in Functions for Reports (Visual Studio Report Designer)
ReportViewer provides built-in functions that you can use in report expressions. Built-in functions can be used in expressions that you include in client report definition (.rdlc) files and in report definition (.rdl) files that are processed on a SQL Server 2005 Reporting Services report server. Support for the functions is provided by the ReportViewer controls and Reporting Services.
Built-in functions are organized into two categories: aggregates and miscellaneous functions. Examples of aggregating data include calculating a sum of all values in a particular field by using the Sum function. You can use aggregate functions in expressions for any report item.
In addition to built-in functions, the expressions that you include in reports can use any Visual Basic function. For more information about Visual Basic functions, see Functions (Visual Basic).
Miscellaneous Functions
The following table describes general purpose functions that you can use.
| Function | Description |
|---|---|
Indicates whether the current instance of an item is within the specified scope. |
|
Returns the current level of depth in a recursive hierarchy. |
|
Returns the previous instance from the specified scope. |
Standard Aggregates
The following table describes the standard aggregate functions that you can use.
| Function | Description |
|---|---|
Returns the average of all non-null values from the specified expression. |
|
Returns a count of the values from the specified expression. |
|
Returns a count of all distinct values from the specified expression. |
|
Returns a count of rows within the specified scope. |
|
Returns the first value from the specified expression. |
|
Returns the last value from the specified expression. |
|
Returns the maximum value from all non-null values of the specified expression. |
|
Returns the minimum value from all non-null values of the specified expression. |
|
Returns the standard deviation of all non-null values of the specified expression. |
|
Returns the population standard deviation of all non-null values of the specified expression. |
|
Returns a sum of the values of the specified expression. |
|
Returns the variance of all non-null values of the specified expression. |
|
Returns the population variance of all non-null values of the specified expression. |
Running Aggregates
The following table describes the running aggregate functions that you can use.
| Function | Description |
|---|---|
Returns a running count of all rows in the specified scope. |
|
Uses a specified function to return a running aggregate of the specified expression. |
Custom Aggregates
The following table describes the custom aggregate function.
| Function | Description |
|---|---|
Returns a custom aggregate of the specified expression, as defined by the data provider. |
Scope
Each aggregate function uses the Scope parameter, which defines the scope in which the aggregate function is performed. A valid scope is the name of a grouping, dataset, or data region. Only groupings or data regions that directly or indirectly contain the expression can be used as a scope. For expressions within data regions, Scope is optional for all aggregate functions. If you omit the Scope parameter, the scope of the aggregate is the innermost data region or grouping to which the report item belongs. Specifying a scope of Nothing sets the scope to the outermost data region to which the report item belongs.
For expressions outside of data regions, Scope refers to a data table or Business object. If a report contains more than one dataset, Scope is required. If a report contains only one dataset and Scope is omitted, the scope is set to the dataset. You cannot specify the Nothing keyword for report items outside of a data region.
You cannot use the Scope parameter in page headers or footers.
See Also
Concepts
Creating Data Sources for a Report
Using Expressions in a Report (Visual Studio Report Designer)
ReportViewer Controls (Visual Studio)
Report Overview (Visual Studio)