//构造sql语句$sql = "update blog_article set title='PHP是世界上最好的语言' where id=1";//或者下面两种,都会自动读取当前设置的表前缀//$sql = "update __PREFIX__article set title='PHP是世界上最好的语言' where id=1";//$sql = "update __ARTICLE__ set title='PHP是世界上最好的语言' where id=1";//实例化model对象,执行execute方法,返回影响行数$res = M()->execute($sql);