ThingkPHP对数据库进行改操作

public function test_check(){
    
     $Experiment = M("Experiment");//实例化Experiment对象。这个对象是跟数据库的表对应的。是对experiment表进行增删改查操作
    //$sno = I(‘sno‘);
    $sno = ‘130906008‘;
    $RowCount = $Experiment -> where("sno = $sno") -> Count();//得到满足条件的行数
    //echo  M("Experiment")->getLastSql(); //打印SQL语句到浏览器界面上
    echo $RowCount;//打印满足条件的行数
    if($RowCount > 0){
     　　$myModel = new \Think\Model();
        $result=$myModel->query("select *from g_experiment where sno = $sno;");
        $this ->ajaxReturn($result);
    }