using System;
using System.Data.Sql;
using System.Data.SqlTypes;
using Microsoft.SqlServer.Server;
using System.IO;

[Serializable]
[SqlUserDefinedAggregate(Format.UserDefined,    
    IsInvariantToNulls = true, 
    IsInvariantToDuplicates = false, 
    IsInvariantToOrder = false, 
    MaxByteSize = 8000)]
public struct TervitavAgregaat:IBinarySerialize{
  public void Init(){}
  public void Accumulate(SqlString vaartus){}
  public void Merge(TervitavAgregaat olemasolev){}
  public SqlString Terminate(){
     return (SqlString)"Tere";
  }
  public void Read(BinaryReader reader){} //Kui oleks vaja vahepealset seisundit talletada
  public void Write(BinaryWriter writer){}
}

/*
D:\kodu\0704>csc /target:library TervitavAgregaat.cs


CREATE ASSEMBLY TervitavAgregaat
FROM 'D:\kodu\0704\TervitavAgregaat.dll'

CREATE AGGREGATE TervitavAgregaat(@vaartus NVARCHAR(200))
RETURNS NVARCHAR(max)
EXTERNAL NAME TervitavAgregaat.TervitavAgregaat

sp_configure 'clr enabled', 1
GO
RECONFIGURE
GO

SELECT dbo.TervitavAgregaat('juku');

Tere

*/