sqlQuery.txt

Yii2.0 增删改查

//关闭csrf  
public $enableCsrfValidation = false;  

1.sql语句  
  
//查询  
  
$db=\Yii::$app->db ->createCommand("select * from 表名") ->queryAll();  
  
//修改  
  
$db=\Yii::$app->db ->createCommand()->update('表名',['字段名'=>要修改的值],'条件') ->execute();  
  
// 删除  
  
$db=\Yii::$app->db ->createCommand() ->delete('表名','条件') ->execute();  
  
 //添加  
  
$db=\Yii::$app->db ->createCommand() ->insert('表名',['字段名'=>要添加的值],'条件') ->execute();  


//应用实例
Customer::find()->one();    此方法返回一条数据；

Customer::find()->all();    此方法返回所有数据；

Customer::find()->count();    此方法返回记录的数量；

Customer::find()->average();    此方法返回指定列的平均值；

Customer::find()->min();    此方法返回指定列的最小值 ；

Customer::find()->max();    此方法返回指定列的最大值 ；

Customer::find()->scalar();    此方法返回值的第一行第一列的查询结果；

Customer::find()->column();    此方法返回查询结果中的第一列的值；

Customer::find()->exists();    此方法返回一个值指示是否包含查询结果的数据行；
Customer::find()->asArray()->one();    以数组形式返回一条数据；

Customer::find()->asArray()->all();    以数组形式返回所有数据；
Customer::find()->where($condition)->asArray()->one();    根据条件以数组形式返回一条数据；

Customer::find()->where($condition)->asArray()->all();    根据条件以数组形式返回所有数据；
Customer::find()->where($condition)->asArray()->orderBy('id DESC')->all();    根据条件以数组形式返回所有数据,并根据ID倒序；

3.关联查询    
    ActiveRecord::hasOne()：返回对应关系的单条记录
 
	ActiveRecord::hasMany()：返回对应关系的多条记录  

应用实例
    

    //客户表Model：CustomerModel   
    //订单表Model：OrdersModel  
    //国家表Model：CountrysModel  
    //首先要建立表与表之间的关系   
    //在CustomerModel中添加与订单的关系  
        
    Class CustomerModel extends yiidbActiveRecord  
    {  
    ...  
      
    public function getOrders()  
    {  
        //客户和订单是一对多的关系所以用hasMany  
        //此处OrdersModel在CustomerModel顶部别忘了加对应的命名空间  
        //id对应的是OrdersModel的id字段，order_id对应CustomerModel的order_id字段  
        return $this->hasMany(OrdersModel::className(), ['id'=>'order_id']);  
    }  
       
    public function getCountry()  
    {  
        //客户和国家是一对一的关系所以用hasOne  
        return $this->hasOne(CountrysModel::className(), ['id'=>'Country_id']);  
    }  
    ....  
    }  
        
    // 查询客户与他们的订单和国家  
    CustomerModel::find()->with('orders', 'country')->all();  
  
    // 查询客户与他们的订单和订单的发货地址  
    CustomerModel::find()->with('orders.address')->all();  
  
    // 查询客户与他们的国家和状态为1的订单  
    CustomerModel::find()->with([  
    'orders' => function ($query) {  
        $query->andWhere('status = 1');  
        },  
        'country',  
    ])->all();  
  注：with中的orders对应getOrders
  
  
常见问题：
1.在查询时加了->select();如下，要加上order_id，即关联的字段（比如：order_id）比如要在select中，否则会报错：undefined index order_id

//查询客户与他们的订单和国家  
CustomerModel::find()->select('order_id')->with('orders', 'country')->all();  
findOne()和findAll():

//查询key值为10的客户  
$customer = Customer::findOne(10);  
$customer = Customer::find()->where(['id' => 10])->one();  

//查询年龄为30，状态值为1的客户  
$customer = Customer::findOne(['age' => 30, 'status' => 1]);  
$customer = Customer::find()->where(['age' => 30, 'status' => 1])->one();  

//查询key值为10的所有客户  
$customers = Customer::findAll(10);  
$customers = Customer::find()->where(['id' => 10])->all();  

//查询key值为10，11,12的客户  
$customers = Customer::findAll([10, 11, 12]);  
$customers = Customer::find()->where(['id' => [10, 11, 12]])->all();  

//查询年龄为30，状态值为1的所有客户  
$customers = Customer::findAll(['age' => 30, 'status' => 1]);  
$customers = Customer::find()->where(['age' => 30, 'status' => 1])->all();  
where()条件：
$customers = Customer::find()->where($cond)->all(); 
$cond写法举例：

//SQL: (type = 1) AND (status = 2).  
$cond = ['type' => 1, 'status' => 2]   
  
//SQL:(id IN (1, 2, 3)) AND (status = 2)  
$cond = ['id' => [1, 2, 3], 'status' => 2]   
  
//SQL:status IS NULL  
$cond = ['status' => null]  
[[and]]:将不同的条件组合在一起，用法举例：

//SQL:`id=1 AND id=2`  
$cond = ['and', 'id=1', 'id=2']  
  
//SQL:`type=1 AND (id=1 OR id=2)`  
$cond = ['and', 'type=1', ['or', 'id=1', 'id=2']]  
[[or]]:

//SQL:`(type IN (7, 8, 9) OR (id IN (1, 2, 3)))`  
$cond = ['or', ['type' => [7, 8, 9]], ['id' => [1, 2, 3]]  
[[not]]:

//SQL:`NOT (attribute IS NULL)`  
$cond = ['not', ['attribute' => null]]  
[[between]]: not between 用法相同

//SQL:`id BETWEEN 1 AND 10`  
$cond = ['between', 'id', 1, 10]  
[[in]]: not in 用法类似
[php] view plain copy
//SQL:`id IN (1, 2, 3)`  
$cond = ['in', 'id', [1, 2, 3]]  
  
//IN条件也适用于多字段  
$cond = ['in', ['id', 'name'], [['id' => 1, 'name' => 'foo'], ['id' => 2, 'name' => 'bar']]]  
  
//也适用于内嵌sql语句  
$cond = ['in', 'user_id', (new Query())->select('id')->from('users')->where(['active' => 1])]  
[[like]]:

//SQL:`name LIKE '%tester%'`  
$cond = ['like', 'name', 'tester']  
  
//SQL:`name LIKE '%test%' AND name LIKE '%sample%'`  
$cond = ['like', 'name', ['test', 'sample']]  
  
//SQL:`name LIKE '%tester'`  
$cond = ['like', 'name', '%tester', false]  
[[exists]]: not exists用法类似

//SQL:EXISTS (SELECT "id" FROM "users" WHERE "active"=1)  
$cond = ['exists', (new Query())->select('id')->from('users')->where(['active' => 1])]  
此外，您可以指定任意运算符如下
[php] view plain copy
//SQL:`id >= 10`  
$cond = ['>=', 'id', 10]  
  
//SQL:`id != 10`  
$cond = ['!=', 'id', 10]  
常用查询：

//WHERE admin_id >= 10 LIMIT 0,10  
p;     User::find()->select('*')->where(['>=', 'admin_id', 10])->offset(0)->limit(10)->all()  

    //SELECT `id`, (SELECT COUNT(*) FROM `user`) AS `count` FROM `post`     
     $subQuery = (new Query())->select('COUNT(*)')->from('user');      
     $query = (new Query())->select(['id', 'count' => $subQuery])->from('post');  

  //SELECT DISTINCT `user_id` ...   
     User::find()->select('user_id')->distinct();  
更新：

//update();  
//runValidation boolen 是否通过validate()校验字段 默认为true   
//attributeNames array 需要更新的字段   
$model->update($runValidation , $attributeNames);    
  
//updateAll();  
//update customer set status = 1 where status = 2  
Customer::updateAll(['status' => 1], 'status = 2');   
  
//update customer set status = 1 where status = 2 and uid = 1;  
Customer::updateAll(['status' => 1], ['status'=> '2','uid'=>'1']);  
删除：

$model = Customer::findOne($id);  
$model->delete();  
  
$model->deleteAll(['id'=>1]);  

批量插入：

    Yii::$app->db->createCommand()->batchInsert(UserModel::tableName(), ['user_id','username'], [  
    ['1','test1'],  
    ['2','test2'],  
    ['3','test3'],     
    ])->execute();  
查看执行sql

//UserModel   
$query = UserModel::find()->where(['status'=>1]);   
echo $query->createCommand()->getRawSql();