Yii的createCommand用法

一、查询

Yii::app()->db->createCommand($sql)->queryAll();//查询所有行数据

​Yii::app()->db->createCommand($sql)->queryRow();//查询第一行数据

​Yii::app()->db->createCommand($sql)->queryColumn();//查询第一列数据​

​Yii::app()->db->createCommand($sql)->queryScalar();//查询第一行的第一字段

二、执行

​Yii::app()->db->createCommand($sql)->execute();//创建、更新、删除，的执行

三、插入insert

$result =Yii::app()->db->createCommand()->insert('table表名', array(

                                   'column1'=>$value1,

                                    'column2'=>$value2,

•                           'column3'=>$value3,
  

                                      'create_time' => time(),            
             )); 

              获取插入id号：Yii::app()->db->getLastInsertID()

四、更新update

​$result =Yii::app()->db->createCommand()->update('table表名', array(  

                                  'column1' => $value1 ,
 

                            'column2' => $value2 , 

                                   'column3'=>$value3,

                             'update_time'=> time(),

                       ),

                         "id=:id",array(':id'=>$id)

          );

五、删除delete

$result =Yii::app()->db->createCommand()->delete('table表名',

                                "id=:id",array(':id'=>$id)

           );

六、select其他写法
单表查询

$goodsTypes = Yii::app()->db->createCommand()
             ->select('type_id, type_name')
             ->from('goods_type')

             ->where('status=1')

              ->queryAll();


连表查询


$goods = Yii::app()->db->createCommand()

        ->from('goods g')
        ->select('g.good_id, g.good_name, gt.type_name, g.price, g.buy_nums, g.commit_nums, g.create_time')
        ->join('goods_type gt', 'g.good_type=gt.type_id')
        ->where('g.`status`=1 and gt.`status`=1')
        ->order('g.create_time desc')
        ->queryAll();

1. // 首先要实例化一个CDbCommand对象  
2. $command = Yii::app()->db->createCommand();     // 注意参数留空了。。  
3. // 可用的方法列表如下：  
4. ->select(): SELECT子句  
5. ->selectDistinct(): SELECT子句，并保持了记录的唯一性  
6. ->from():         构建FROM子句  
7. ->where():        构建WHERE子句  
8. ->join():         在FROM子句中构建INNER JOIN 子句  
9. ->leftJoin():     在FROM子句中构建左连接子句  
10. ->rightJoin():    在FROM子句中构建右连接子句  
11. ->crossJoin():    添加交叉查询片段(没用过)  
12. ->naturalJoin():  添加一个自然连接子片段  
13. ->group():        GROUP BY子句  
14. ->having():       类似于WHERE的子句，但要与GROUP BY连用  
15. ->order():        ORDER BY子句  
16. ->limit():        LIMIT子句的第一部分  
17. ->offset():       LIMIT子句的第二部分  
18. ->union():        appends a UNION query fragment
    
19. 
    

举个实际的例子吧：

//查询列表
$command=Yii::app()->db->createCommand();
$command->select("a.*,b.user_name as create_user, e.department_name, c.supplier_name,c.supplier_operator,c.supplier_product,d.bank_name");
$command->from("ab_supplier_refund a");
$command->Leftjoin("ab_user b","a.create_user_id = b.id");
$command->Leftjoin("ab_suppliers c","a.supplier_id = c.supplier_id");
$command->Leftjoin("ab_bank d","a.bank_id = d.id");
$command->Leftjoin("ab_department e","b.user_department = e.id");
$command->andwhere("a.status != -1");
if(isset($where['start_time'])) {
    $command->andwhere("a.create_time >= " . $where['start_time']);//开始时间
}
if(isset($where['end_time'])) {
    $command->andwhere("a.create_time <= " . $where['end_time']);//结束时间
}
if(isset($where['search_all'])) {
    $search_all = strtr($where['search_all'], array('%'=>'\%', '_'=>'\_'));
    $in_int=intval($search_all);
    $command->andwhere("a.id ={$in_int} or b.user_name like '%{$search_all}%' or c.supplier_name like '%{$search_all}%' or c.supplier_operator in {$where['supplier_operator_or']} or c.supplier_product like '%{$search_all}%' or d.bank_name like '%{$search_all}%' ");
}
if(isset($where['refund_status'])) {
    $command->andwhere("a.status = " . $where['refund_status']);
}
if(isset($where['refund_id'])) {
    $command->andwhere("a.id = " . $where['refund_id']);
}
if(isset($where['create_user'])) {
    $command->andwhere("b.user_name like " . $where['create_user']);
}
if(isset($where['supplier_name'])) {
    $command->andwhere("c.supplier_name like " . $where['supplier_name']);
}
if(isset($where['supplier_operator'])) {
    $command->andwhere("c.supplier_operator = " . $where['supplier_operator']);
}
if(isset($where['supplier_product'])) {
    $command->andwhere("c.supplier_product like " . $where['supplier_product']);
}
if(isset($where['bank_name'])) {
    $command->andwhere("d.bank_name like " . $where['bank_name']);
}
if(isset($where['bank_id'])) {
    $command->andwhere("d.id = " . $where['bank_id']);
}

//排序条件
if(isset($order['refund_id'])){
    $command->order(" a.id ".$order['refund_id']);
}
if(isset($order['create_time'])){
    $command->order(" a.create_time ".$order['create_time']);
}

$command->limit($length, $start);
$list=$command->queryAll();

一般这样调用：