SqlMethodAttribute Class

Definition

Namespace:

Microsoft.Data.SqlClient.Server

Assembly:

Microsoft.Data.SqlClient.dll

Package:

Microsoft.Data.SqlClient v4.1.0

Indicates the determinism and data access properties of a method or property on a user-defined type (UDT). The properties on the attribute reflect the physical characteristics that are used when the type is registered with SQL Server.

public ref class SqlMethodAttribute sealed : Microsoft::Data::SqlClient::Server::SqlFunctionAttribute

[System.AttributeUsage(System.AttributeTargets.Method, AllowMultiple=false, Inherited=false)]
public sealed class SqlMethodAttribute : Microsoft.Data.SqlClient.Server.SqlFunctionAttribute

[<System.AttributeUsage(System.AttributeTargets.Method, AllowMultiple=false, Inherited=false)>]
type SqlMethodAttribute = class
    inherit SqlFunctionAttribute

Public NotInheritable Class SqlMethodAttribute
Inherits SqlFunctionAttribute

Inheritance

Attribute

SqlFunctionAttribute

SqlMethodAttribute

Attributes

AttributeUsageAttribute

Examples

The following example shows a UDT method that is attributed to indicate that the method will not be invoked on null instances of the type, that the method will not change the state of the type, and that the method will not be called when null parameters are supplied to the method invocation.

using Microsoft.Data.SqlClient.Server;
using System.Data.SqlTypes;
using System.Text;

[Serializable]
[Microsoft.Data.SqlClient.Server.SqlUserDefinedType(Format.Native,
     IsByteOrdered = true,
     Name = "Point", ValidationMethodName = "ValidatePoint")]
public struct Point : INullable
{

    private bool is_Null;
    private Int32 _x;
    private Int32 _y;

    // Distance from Point to the specified x and y values method.
    [SqlMethod(OnNullCall = false, IsMutator = false, InvokeIfReceiverIsNull = false)]
    public Double DistanceFromXY(Int32 iX, Int32 iY)
    {
        return Math.Sqrt(Math.Pow(iX - _x, 2.0) + Math.Pow(iY - _y, 2.0));
    }

Remarks

For a property, the SqlMethodAttribute should be used on the setter or the getter directly.

SqlMethodAttribute inherits from a SqlFunctionAttribute, so SqlMethodAttribute inherits the FillRowMethodName and TableDefinition fields from SqlFunctionAttribute. Note that it is not possible to write a table-valued method, although the names of these fields might suggest that it is possible.

Constructors

SqlMethodAttribute()

An attribute on a user-defined type (UDT), used to indicate the determinism and data access properties of a method or a property on a UDT.

Properties

DataAccess	Indicates whether the function involves access to user data stored in the local instance of SQL Server. (Inherited from SqlFunctionAttribute)
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. (Inherited from SqlFunctionAttribute)
InvokeIfReceiverIsNull	Indicates whether SQL Server should invoke the method on null instances.
IsDeterministic	Indicates whether the user-defined function is deterministic. (Inherited from SqlFunctionAttribute)
IsMutator	Indicates whether a method on a user-defined type (UDT) is a mutator.
IsPrecise	Indicates whether the function involves imprecise computations, such as floating point operations. (Inherited from SqlFunctionAttribute)
Name	The name under which the function should be registered in SQL Server. (Inherited from SqlFunctionAttribute)
OnNullCall	Indicates whether the method on a user-defined type (UDT) is called when null input arguments are specified in the method invocation.
SystemDataAccess	Indicates whether the function requires access to data stored in the system catalogs or virtual system tables of SQL Server. (Inherited from SqlFunctionAttribute)
TableDefinition	A string that represents the table definition of the results, if the method is used as a table-valued function (TVF). (Inherited from SqlFunctionAttribute)