Interface IAggregator

Performs actual grouping and analytical operations on data. Aggregator can perform following operations: Average, Sum, Min, Max, Count, Distinct. If result after aggregation execution is null than default value of built in Aggregator for that specific type is returned. Custom aggregator, for custom data types and custom functions like Mean, Median, Mode can also be implementated.

Namespace:
Assembly: Alachisoft.NCache.Runtime.dll
Syntax
public interface IAggregator

Aggregate(Object)

Performs given logic of aggregation on a on local node like combiner.

Declaration
object Aggregate(object value)
Parameters
Type Name Description
System.Object value

object
Returns
Type Description
System.Object

Retuns aggregated result.
Examples

Following example illustrate the implementation of Aggregate. 

string function;
//setting current aggregator function

public IntAggregator(string function)
{
   this.function = function;
}

//Implementing interface function

public object Aggregate(object value)
{
   return calculate(value);
}
//Function to calculate values

private object calculate(object value)
{
   switch (function)
   {
       case "MIN":
           value = int.MinValue;
           return value;
       case "MAX":
           value = int.MaxValue;
           return value;
       default:
           return 0;
   }
}

AggregateAll(Object)

Performs given logic of aggregation on server nodes like Reduce phase operation.

Declaration
object AggregateAll(object value)
Parameters
Type Name Description
System.Object value

object
Returns
Type Description
System.Object

Retuns aggregated result.
Examples

Following example illustrate the implementation of Aggregate. 

string function;
//setting current aggregator function

public IntAggregator(string function)
{
   this.function = function;
}

//Implementating interface function

public object AggregateAll(object value)
{
   return calculate(value); //implement inside logic.
}
//Function to calculate values

private object calculate(object value)
{
   switch (function)
   {
       case "MIN":
           value = int.MinValue;
           return value;
       case "MAX":
           value = int.MaxValue;
           return value;
       default:
           return 0;
   }
}