SELECT * FROM class_stu m where 'add_time'<=1292169600 and 'add_time'>1292083200 order by m.add_time DESC LIMIT 0, 20 查询字段不应该加单引号的,SELECT * FROM class_stu m where add_time<=1292169600 and add_time>1292083200 order by m.add_time DESC LIMIT 0, 20 ,这样就对了