Method Aggregate

Aggregate(IValueExtractor, IAggregator, IKeyFilter, QueryCommand, Int32)

Built upon MapReduce framework, processes distributed data records to return compiled and statistical results for analytical purposes.

Declaration
[Obsolete("This feature is not in active development and may be removed in a future update.")]
object Aggregate(IValueExtractor extractor, IAggregator aggregator, IKeyFilter keyFilter = null, QueryCommand queryCommand = null, int timeout = 2147483647)
Parameters
Type Name Description
IValueExtractor extractor

Implementation of IValueExtractor to extract the meaningful attributes from given objects.
IAggregator aggregator

IAggregator For actual grouping and analytical operations on given data using Map Reduce Combiner and Reducer.
IKeyFilter keyFilter

Instance of IKeyFilter implementation.
QueryCommand queryCommand

Instance of QueryCommand containing query and values.
System.Int32 timeout

Time in millisecond in which if result is not returned, thread will be terminated and exception or null will be given.
Returns
Type Description
System.Object

Returns a single result depending upon given extractor.
Examples
ICache cache = CacheManager.GetCache("demoClusteredCache");

string key1 = "2202";

Product product1 = new Product()
{
    Id = 4,
    Category = "Clothes",
    UnitPrice = 4,
    UnitsAvailable = 2
};

string key2 = "2203";
Product product2 = new Product()
{
    Id = 4,
    Category = "Shoes",
    UnitPrice = 5,
    UnitsAvailable = 9
};

cache.Add(key1, product1);
cache.Add(key2, product2);

string query = "SELECT Alachisoft.NCache.Sample.Data.Product WHERE this.Category=?";
QueryCommand queryCommand = new QueryCommand(query);
queryCommand.Parameters.Add("Category", "Clothes");

object result = cache.ExecutionService.Aggregate(new BasicTypeExtractor(), BuiltInAggregator.Count(), null, queryCommand, 50000);