TP5关联模板查询

ThinkPHP5有关联模型的操作

hasOne：有一个，加上主谓语应该是 ，A 有一个 B
hasMany：有很多，A 有很多 B
belongsTo：属于， A 属于 B
belongsToMany：多对多

一对一：HAS_ONE  以及对应的BELONEGS_TO
一对多：HAS_MANY 以及相对的BELONGS_TO
多对多：BELONGS_TO_MANY

确立关联模型

在关系型数据库中，表之间有一对一、一对多、多对多的关系。在 TP5 中，实现了ORM (Object Relational Mapping) 的思想，通过在模型中建立模型间的关联，实现建立表与表之间的关联

建立E-R图

一对一

class User extends Model{
   //定义关联方法
   public function profile(){
     return $this->hasOne('Profile','user_id','id');
   }
}

class Profile extends Model{
    public function user(){
      return $this->belongsTo('User');
    }
}

#使用
public function add(){
        $user = new UserModel;    
        $user->name = 'thinkphp';
        $user->password = '123456';
        $user->nickname = '宝宝不舒服';
        if($user->save()){
            $profile['truename'] = '宝宝不舒服';
            $profile['birthday'] = '1989-03-05';
            $profile['address']  = '深圳';
            $user->profile()->save($profile);
            return $this->success('添加成功');
        }else{
            return $user->getError();
        }
}

public function read($id){
    $user = UserModel::get($id);
    if($user){
      echo  $user->name;
      echo  $user->nickname;
      echo  $user->profile->truename;
    }
}
public function update($id){
   $user = UserModel::get($id);
   $user->name = 'framework';
   if($user->save()){
      $user->profile->email = '609392790@qq.com';
      $user->profile->save();

    }else{
        return $user->getError();
    }

}
public  function delete($id){
    $user = UserModel::get($id);
    if($user->delete()){
        $user->profile->delete();
     }else{
       return $user->getError();
     }
}

一对多

class User extends Model{
  public  function books(){
   return $this->hasMany('Book');
  }

}
class Book extends Model{
  public function user(){
     return $this->belongsTo('User');
  }
}

#使用
public function addBook(){
    $user = UserModel::get(1);
    $book = new Book;
    $book->title = 'thinkphp';
    $book->publih_time = '2016-05-06';
    $user->books()->save($book);
}
public  function batchAddBook(){
   $user = UserModel::get(1);
   $book = [
     ['title'=>'thinkphp5.0','publish'=>'2016-05-06'],
     ['title'=>'thinkphp3.2','publish'=>'2014-05-06']
   ];
    $user->books()->saveAll($books);
}
public function read(){
  $user = UserModel::get(1);
  $books = $user->books()->where('status',1)->select();
  $book  = $user->books()->getByTitle('宝宝想哭');
}
public function read(){
  //查询写过书的作者列表
  $user = UserModel::has('books')->select();
  //查询写过三本书以上的作者
  $user = UserModel::has('books','>=',3)->select();
  //查询写过宝宝不哭的作者
  $user = UserModel::hasWhere('books',['title'=>'宝宝不哭'])->select();
}
public  function update($id){
  $user = UserModel::get($id);
  $book = $user->books()->where('title','宝宝不哭')->update(['title'=>'宝宝就要哭']);
}
public function delete($id){
   $user = UserModel::get($id);
   $book = $user->books()->getByTitle('Thinkphp');
   $book->delete();
}

多对多

public function roles(){
  return $this->belongsToMany('Role','Think_access');
}

public function user(){
  return $this->belongsToMany('User','think_access');
}

#使用
public function add(){
   $user = UserModel::getByNickname('张三');
   $user->roles()->save(['name'=>'editor','title'=>'编辑']);
}
public function add(){
   $user = UserModel::getByNickname('张三');
   $user->roles->saveAll([
     ['name'=>'leader','title'=>'领导'],
     ['name'=>'admin','title'=>'管理员'],
  ]);
}

public function delete(){
   $usr = UserModel::get(2) ;
   $role = Role::getByName('admin');
   $user->roles()->detach($role);
   //$user->roles()->detach($role,true);
}

例子

class Category extends Model
{
    public function product(){
        return $this->hasMany('product','category_id','id');
    }
}
class Product extends Model
{
    public function property(){
        return $this->hasMany('property','goods_id','id');
    }
}


#使用
public function index()
{
    return Category::with('product,product.property')->where('id',1)->find();
}
class Category extends Model
{
    public function product(){
        return $this->hasMany('product','category_id','id');
    }

    public function list(){
        //在with中可以传递一个闭包函数，函数的参数为当前key锁对应模型的查询器 $this
        //在闭包函数中无需使用select或者find等返回数据
        //如下操作返回 category中所有值，以及对应 product ，并且product按照price排序
        return self::with([
            'product'=>function($query){
                $query->with('property')->field('name')->order('price');
            }
        ])->select();
    }
}

注意

//这个可以过滤条件，但是不能处理分页
$model->with(['adminUsers'=>function($query){
  $query->where("type",$this->param['type']);
}]);

//又要有条件又分页, join适用于一对一的关系表合并
$model->alias('a')
      ->join('admin_users u','a.admin_id = u.id','LEFT')
      ->where('u.type',$this->param['type']);