修改发布时间不超过发文时间6天

UPDATE  dbo.T_ARTICLE
        SET     PUBLISH_TIME = DATEADD(DAY,
                                       6 - DATEDIFF(day, FILE_TIME,
                                                    PUBLISH_TIME),
                                       PUBLISH_TIME)
        WHERE   PUBLISH_TIME >= '2014/01/06'
                AND FILE_TIME IS NOT NULL
                AND DATEDIFF(DAY, FILE_TIME, PUBLISH_TIME) > 7