SqlFunctionAttribute SqlFunctionAttribute SqlFunctionAttribute SqlFunctionAttribute Class

Definition

Used to mark a method definition of a user-defined aggregate as a function in SQL Server. The properties on the attribute reflect the physical characteristics used when the type is registered with SQL Server.

public ref class SqlFunctionAttribute : Attribute
[System.AttributeUsage(System.AttributeTargets.Method, AllowMultiple=false, Inherited=false)]
[System.Serializable]
public class SqlFunctionAttribute : Attribute
type SqlFunctionAttribute = class
    inherit Attribute
Public Class SqlFunctionAttribute
Inherits Attribute
Inheritance
SqlFunctionAttributeSqlFunctionAttributeSqlFunctionAttributeSqlFunctionAttribute
Derived
Attributes

Examples

The following example shows an aggregate function that returns a list of files in the specified directory path.

[SqlFunctionAttribute(FillRowMethodName = "FillFileRow")]
public static IEnumerable GetFileDetails(string directoryPath)
{
   try
   {
      DirectoryInfo di = new DirectoryInfo(directoryPath);
      return di.GetFiles();
   }
   catch (DirectoryNotFoundException dnf)
   {
      return new string[1] { dnf.ToString() };
   }
			
}
<SqlFunction(FillRowMethodName:="FillFileRow")> _
Public Shared Function GetFileDetails(ByVal directoryPath As String) As IEnumerable

   Try

      Dim di As DirectoryInfo = new DirectoryInfo(directoryPath)
      return di.GetFiles()
   
   Catch dnf As DirectoryNotFoundException

      Dim message As String() = {dnf.ToString() }
      return message

   End Try
End Function

Constructors

SqlFunctionAttribute() SqlFunctionAttribute() SqlFunctionAttribute() SqlFunctionAttribute()

An optional attribute on a user-defined aggregate, used to indicate that the method should be registered in SQL Server as a function. Also used to set the DataAccess, FillRowMethodName, IsDeterministic, IsPrecise, Name, SystemDataAccess, and TableDefinition properties of the function attribute.

Properties

DataAccess DataAccess DataAccess DataAccess

Indicates whether the function involves access to user data stored in the local instance of SQL Server.

FillRowMethodName FillRowMethodName FillRowMethodName FillRowMethodName

The name of a method in the same class which is used to fill a row of data in the table returned by the table-valued function.

IsDeterministic IsDeterministic IsDeterministic IsDeterministic

Indicates whether the user-defined function is deterministic.

IsPrecise IsPrecise IsPrecise IsPrecise

Indicates whether the function involves imprecise computations, such as floating point operations.

Name Name Name Name

The name under which the function should be registered in SQL Server.

SystemDataAccess SystemDataAccess SystemDataAccess SystemDataAccess

Indicates whether the function requires access to data stored in the system catalogs or virtual system tables of SQL Server.

TableDefinition TableDefinition TableDefinition TableDefinition

A string that represents the table definition of the results, if the method is used as a table-valued function (TVF).

TypeId TypeId TypeId TypeId

When implemented in a derived class, gets a unique identifier for this Attribute.

(Inherited from Attribute)

Methods

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

Returns a value that indicates whether this instance is equal to a specified object.

(Inherited from Attribute)
GetHashCode() GetHashCode() GetHashCode() GetHashCode()

Returns the hash code for this instance.

(Inherited from Attribute)
GetType() GetType() GetType() GetType()

Gets the Type of the current instance.

(Inherited from Object)
IsDefaultAttribute() IsDefaultAttribute() IsDefaultAttribute() 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) Match(Object) Match(Object) Match(Object)

When overridden in a derived class, returns a value that indicates whether this instance equals a specified object.

(Inherited from Attribute)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString() ToString() ToString() ToString()

Returns a string that represents the current object.

(Inherited from Object)

Explicit Interface Implementations

_Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr) _Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr) _Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr) _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) _Attribute.GetTypeInfo(UInt32, UInt32, IntPtr) _Attribute.GetTypeInfo(UInt32, UInt32, IntPtr) _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) _Attribute.GetTypeInfoCount(UInt32) _Attribute.GetTypeInfoCount(UInt32) _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) _Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr) _Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr) _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