thinkphp 3.2 视图模型 生成的SQL语句提示 1267错误 求指点~

用的TP3.2 视图模型 查询 
模型里是这样写的 
PicViewModel.class.php

<?phpnamespace Home\Model;use Think\Model\ViewModel;class PicViewModel extends  ViewModel{    public $viewFields =array(       'Picture'=> array('picTitle','picToken','picCategroy','picAuthor','picPostTime','_as'=>'Picture'),        'PictureAttachment' =>array('pictureid','pictureurl','creattime','_on'=>'Picture.picToken = PictureAttachment.pictureid','_as'=>'PictureAttachment'),    );}

控制器这样写

  public function  Pic(){         $PicModel =D('PicView');            $s1= $PicModel->field('picTitle,picCategroy,picAuthor,picPostTime,pictureurl')->order('picPostTime desc')->select();        dump($PicModel->getLastSql());        dump($s1);    }

生成的SQL 语句是这样的

SELECT Picture.picTitle AS picTitle,Picture.picCategroy AS picCategroy,Picture.picAuthor AS picAuthor,Picture.picPostTime AS picPostTime,PictureAttachment.pictureurl AS pictureurl FROM xxx_picture Picture  JOIN xxx_picture_attachment PictureAttachment ON Picture.picToken = PictureAttachment.pictureid ORDER BY Picture.picPostTime desc

在phpmyadmin里运行出现
MySQL 返回： 文档

#1267 - Illegal mix of collations (utf8_general_ci,IMPLICIT) and (utf8_unicode_ci,IMPLICIT) for operation '=' 
这个应该是排序规则不同  然后我在phpmyadmin里直接修改表的
改成一样是utf8_general_ci,了 还是报错 

网上查了是这样执行
alert xxx_picture_attachment CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci
ALTER xxx_picture_attachment DEFAULT CHARACTER SET utf8_general_ci
貌似也不行额
报错
MySQL 返回： 文档

#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'alert xxx_picture_attachment CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_' at line 1 

求大神指点下啊

回复讨论(解决方案)

贴出表结构看看

贴出表结构看看

谢谢提醒 原来是字段的排序问题 谢谢 了~