使用SQL语句修改表说明

在Sql Server 2008中修改表备注，存储过程语句如下：

ALTER PROCEDURE [dbo].[SetTableDescription]
    @des VARCHAR(500) ,
    @tablename VARCHAR(100)
AS 
    IF ( NOT EXISTS ( SELECT    1
                      FROM      sys.objects a
                                INNER JOIN sys.extended_properties b ON a.object_id = b.major_id
                                                              AND b.minor_id = 0
                      WHERE     a.name = @tablename )
       ) 
        BEGIN
            EXEC sys.sp_addextendedproperty @name = N'MS_Description',
                @value = @des, @level0type = N'SCHEMA', @level0name = N'dbo',
                @level1type = N'TABLE', @level1name = @tablename
        END