Реферат: MS SQL Server 9 Yukon. Интеграция с .NET

[Serializable]

[SqlUserDefinedAggregate(Format.Native, IsInvariantToDuplicates = false, IsInvariantToNulls = true, IsInvariantToOrder = true, IsNullIfEmpty = true)]

[StructLayout(LayoutKind.Sequential)]

public class AvgGeom: INullable

{

private double _agg;

private int _count;

private bool _isNull = true;

#region User-Defined Attribute Required Methods

public void Init()

{

_agg = 0;

_count = 0;

_isNull = true;

}

public void Accumulate(SqlDouble Value)

{

if (!Value.IsNull)

{

_agg += System.Math.Log(Value.Value);

_count++;

_isNull = false;

}

}

public void Merge(AvgGeom Group)

{

if (!Group.IsNull)

{

_agg += Group._agg;