Rollup attributes support a CalculateRollupField message that developers can use to calculate a rollup attribute value on demand. The request and response, along with the members, are shown in the following table.
Target: EntityReference for the record.
FieldName: String representing the logical name of the attribute.
Entity: Entity containing the rollup attribute and the supporting <attribute SchemaName>_Date and <attribute SchemaName>_State attributes.
This message is a synchronous operation for just the attribute identified in the request. If the value of that record is included as part of other rollup fields, the values of those fields won’t take the possible value change caused by calling this method into consideration until the regularly scheduled asynchronous jobs that perform those calculations occur.
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