本文以实例形式展示了Yii使用find findAll查找出指定字段的实现方法,分享给大家供大家参考之用。具体方法如下:
总所周知,采用如下方法:
modelName::model() -> find() //找出的是一个对象 modelName::model() -> findALL() //找出的是一个对象集合的数组
可以找出对象与对象集合的数组,那么如何找出我所需要的字段的数据,而不是全部字段的数据呢?之前我是这么做的:
$criteria = new CDbCriteria; $criteria->select = 'username,id,email'; $criteria->order = 'id DESC'; $users = modelName::model()->findAll( $criteria );
后台无意中看到别人有这么写的,方法很不错:
$users = modelName::model()->findAll(array( 'select' =>array('username','id','email'), 'order' => 'id DESC', ));
测试后发现果然可以用,那么find也可以这么操作:
$user = modelName::model()->find(array( 'select' =>array('username','id','email'), 'order' => 'id DESC', 'condition' => 'id='.$id, ));
当然了,这么做肯定不安全了,换成下面的方法同样可以:
$users = $this->user->find(array( 'select'=>array('id','username','email'), 'order' => 'id DESC', 'condition' => 'state=:state AND id=:id', 'params' => array(':state'=>'1',':id' => '2'), ));
同理用findAll测试了也可以。
结论:
通过这种方法能够很方便的获取所需要的数据,当然需要分页的时候还是 需要 new 一下 CDbCriteria 的。
希望本文所述对大家采用Yii进行数据库程序设计能有所帮助。

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