The AggregateFilter defines the Aggregate function that should be used to calculate the values to be returned. The AggregateFilte r is formally defined in OPC 10000-4. Table 7 outlines the components of the AggregateFilter structure for the purposes of discussion in this document.
Table 7 – AggregateFilter structure
| 
 Name  | 
        
 Description  | 
| 
 AggregateFilter  | 
        
 
  | 
| 
 startTime  | 
        
 Beginning of period to calculate the Aggregate the first time.  | 
| 
 aggregateType  | 
        
 The NodeIds of the AggregateFunction Objects that indicates the list of Aggregates to be used when retrieving processed data.  | 
| 
 processingInterval  | 
        
 The period to be used to compute the Aggregate.  | 
| 
 aggregateConfiguration  | 
        
 This parameter allows Clients to override the Aggregate configuration settings supplied by an AggregateConfiguration Object on a per monitored item basis.  | 
| 
 useServerDefaults  | 
        
 If True the Server’s default values are used and any values specified for the other parameters are ignored.  | 
| 
 treatUncertainAsBad  | 
        
 See 4.2.1.2.  | 
| 
 percentDataBad  | 
        
 See 4.2.1.2.  | 
| 
 percentDataGood  | 
        
 See 4.2.1.2.  | 
| 
 useSlopedExtrapolation  | 
        
 See 4.2.1.2.  |