Aggregate Functions in Calculated Fields - Usage Example

This example shows a report that uses aggregate functions in calculated fields. For each product, the report calculates the percentage of total revenue computed for all products that belong to a certain category. The report also counts the number of products in a category that are not discontinued and have revenue greater than $500.

The aggregate expression has the following format:

[<Collection>][<Condition>].<Aggregate>(<Expression>)

• <Collection> - Specifies a collection for which an aggregated value is calculated. It can be the relationship name for a master-detail relationship, or a collection property name exposed by the target class. Empty brackets [] indicate the root collection.
• <Condition> - Specifies a condition that filters records for calculation. If the condition and its surrounding brackets are omitted, an aggregated value is calculated for all records (for example, [].Count()).
• <Aggregate> - Specifies an aggregate function.
• <Expression> - Specifies the expression being calculated. The expression contains field values (for example, [][[CategoryID] > 5].Sum([UnitPrice]*[Quantity])). Note that the Count function does not require arguments, and the expression is omitted in this case. Use the Parent Relationship Traversal Operator ('^') to refer to the processed group (for example[][[^.CategoryID] == [CategoryID]].Sum([UnitPrice])). This operator allows you to calculate aggregates within groups.

Expressions used in this example are shown in the picture below:

Documentation

• Use Calculated Fields
• Use Expressions
• Aggregate Enum

More Examples

• How to create a calculated field at runtime

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