SQL Server 2005 自动更新日期时间列 - LastUpdated

I have a table defined (see code snippet below). How can I add a constraint or whatever so that the LastUpdate column is automatically updated anytime the row is changed?

CREATE TABLE dbo.Profiles
(
        UserName                                varchar(100)            NOT NULL,
        LastUpdate                              datetime                NOT NULL  CONSTRAINT DF_Profiles_LastUpdate DEFAULT (getdate()),
        FullName                                varchar(50)             NOT NULL,
        Birthdate                               smalldatetime           NULL,
        PageSize                                int                     NOT NULL CONSTRAINT DF_Profiles_PageSize DEFAULT ((10)),
        CONSTRAINT PK_Profiles PRIMARY KEY CLUSTERED (UserName ASC),
        CONSTRAINT FK_Profils_Users FOREIGN KEY (UserName) REFERENCES dbo.Users (UserName) ON UPDATE CASCADE ON DELETE CASCADE  
)

推荐答案

默认约束只适用于插入；对于更新，请使用触发器.