SqlUserDefinedAggregateAttribute Class

Definition

Namespace:: Microsoft.SqlServer.Server

Assembly:: System.Data.SqlClient.dll

Assembly:: System.Data.dll

Indicates that the type should be registered as a user-defined aggregate. The properties on the attribute reflect the physical attributes used when the type is registered with SQL Server. This class cannot be inherited.

public ref class SqlUserDefinedAggregateAttribute sealed : Attribute

[System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Struct, AllowMultiple=false, Inherited=false)]
public sealed class SqlUserDefinedAggregateAttribute : Attribute

[<System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Struct, AllowMultiple=false, Inherited=false)>]
type SqlUserDefinedAggregateAttribute = class
    inherit Attribute

Public NotInheritable Class SqlUserDefinedAggregateAttribute
Inherits Attribute

Inheritance: Object

Attribute
SqlUserDefinedAggregateAttribute

Attributes: AttributeUsageAttribute

Examples

The following example shows the SqlUserDefinedAggregateAttribute attribute for a user-defined aggregate. The aggregate uses custom serialization, has a maximum size of 8000 bytes when serialized, and is invariant to nulls, duplicates, and order.

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

[Serializable]
[Microsoft.SqlServer.Server.SqlUserDefinedAggregate(
   Microsoft.SqlServer.Server.Format.UserDefined,
   IsInvariantToNulls = true,			
   IsInvariantToDuplicates = false,		
   IsInvariantToOrder = false,			
   MaxByteSize = 8000)				
        ]
public class Concatenate : Microsoft.SqlServer.Server.IBinarySerialize
{

Imports System.Data
Imports System.IO
Imports Microsoft.SqlServer.Server

<Serializable(), SqlUserDefinedAggregate(Microsoft.SqlServer.Server.Format.UserDefined, _ 
                                         IsInvariantToNulls:=True, _ 
                                         IsInvariantToDuplicates:=False, _
                                         IsInvariantToOrder:=False, _
                                         MaxByteSize:=8000)> _
Public Class Concatenate
    Implements Microsoft.SqlServer.Server.IBinarySerialize

Remarks

SQL Server creates a user-defined aggregate that is bound to the class definition that has the SqlUserDefinedAggregateAttribute custom attribute. Every user-defined aggregate must be annotated with this attribute.

See "CLR User-Defined Aggregates" in SQL Server 2005 Books Online for more information on user-defined aggregates and examples.

Constructors

SqlUserDefinedAggregateAttribute(Format)

A required attribute on a user-defined aggregate, used to indicate that the given type is a user-defined aggregate and the storage format of the user-defined aggregate.

Fields

MaxByteSizeValue

The maximum size, in bytes, required to store the state of this aggregate instance during computation.

Properties

Format	The serialization format as a Format.
IsInvariantToDuplicates	Indicates whether the aggregate is invariant to duplicates.
IsInvariantToNulls	Indicates whether the aggregate is invariant to nulls.
IsInvariantToOrder	Indicates whether the aggregate is invariant to order.
IsNullIfEmpty	Indicates whether the aggregate returns `null` if no values have been accumulated.
MaxByteSize	The maximum size, in bytes, of the aggregate instance.
Name	The name of the aggregate.
TypeId	When implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute)

Methods

Equals(Object)	Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute)
GetHashCode()	Returns the hash code for this instance. (Inherited from Attribute)
GetType()	Gets the Type of the current instance. (Inherited from Object)
IsDefaultAttribute()	When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute)
Match(Object)	When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)

Explicit Interface Implementations

_Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr)	Maps a set of names to a corresponding set of dispatch identifiers. (Inherited from Attribute)
_Attribute.GetTypeInfo(UInt32, UInt32, IntPtr)	Retrieves the type information for an object, which can be used to get the type information for an interface. (Inherited from Attribute)
_Attribute.GetTypeInfoCount(UInt32)	Retrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from Attribute)
_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)	Provides access to properties and methods exposed by an object. (Inherited from Attribute)

Applies to