tp5数据库的查询、增添、更新、删除数据

<?phpnamespace app\home\controller;use think\Request;class Test{    public function index()    {//查询       $result=db("test")->select();       dump($result);       $test=array(           "name"=>"youshe",           "sex"=>"男",       );           db("test")->insert($test);//  //删除//$test["id"]="3";//db("test")->where($test)->delete();//////更新//        $updatawhere["id"]="5";//        $updata["name"]="genxing";//        db("test")->where($updatawhere)->update($updata);        //添加单条查询        $nihao["id"]="6";        $dantiao=db("test")->where($nihao)->select();      dump($dantiao);    }}