注:$c = new CDbCriteria();是ActiveRecord的一种写法,使ActiveRecord更加灵活。
Yii的Active Recorder包装了很多。
特别是把SQL中 把where,order,limit,IN/not IN,like等常用短句都包含进CDbCriteria这个类中去,这样整个代码会比较规范,一目了然。
$criteria =newCDbCriteria;
$criteria->addCondition(“id=1”); //查询条件,即where id =1
$criteria->addInCondition(‘id’, array(1,2,3,4,5));//代表where id IN (1,23,,4,5,);
$criteria->addNotInCondition(‘id’,array(1,2,3,4,5));//与上面正好相法,是NOT IN
$criteria->addCondition(‘id=1′,’OR’);//这是OR条件,多个条件的时候,该条件是OR而非AND
$criteria->addSearchCondition(‘name’,’分类’);//搜索条件,其实代表了。。where name like ‘%分类%’
$criteria->addBetweenCondition(‘id’, 1, 4);//between1 and 4
$criteria->compare(‘id’,1); //这个方法比较特殊,他会根据你的参数自动处理成addCondition或者addInCondition,
//即如果第二个参数是数组就会调用addInCondition
$criteria->addCondition(“id = :id”);
$criteria->params[‘:id’]=1;
$criteria->select = ‘id,parentid,name’;//代表了要查询的字段,默认select=’*’;
$criteria->join = ‘xxx’; //连接表
$criteria->with = ‘xxx’;//调用relations
$criteria->limit =10; //取1条数据,如果小于0,则不作处理
$criteria->offset =1; //两条合并起来,则表示 limit 10 offset1,或者代表了。limit 1,10
$criteria->order = ‘xxx DESC,XXX ASC’ ;//排序条件
$criteria->group = ‘group 条件’;
$criteria->having = ‘having 条件 ‘;
$criteria->distinct = FALSE;//是否唯一查询
实例:
Php代码
$criteria = new CDbCriteria();
$criteria->select = ‘table_name,model_id,sum(amount) total’;
$criteria->group = ‘table_name,model_id’;
$criteria->addCondition(“$nIdcId=4”);//也可以$criteria->condition = “$nIdcId=4″;
$aResult = accessory_info::model()->findAll($criteria);
$c = new CDbCriteria();
$c->select = ‘t.id, t.created_at, t.outsource_id, t.user_id, t.operate, t.content’;
$c->join = ‘LEFT JOIN outsource ON outsource.id=t.outsource_id’;
$c->condition = ‘outsource.idc_id IN(‘ . implode(‘,’, $idc_ids) . ‘)’;
if($last_log_id) {
$c->condition .= ” AND t.id > $last_log_id”;
}
$c->limit = 20;
$c->order = ‘t.id DESC’;
$logs = OutsourceProcessLog::model()->findAll($c);
批注:
1,与DAO方式结果区别是:DAO方式 数组中的每一个元素仍是数组。而通过CDbCriteria方式,数组中的元素是对象。
2,即使该功能很强大,仍有一些需求不能满足,此时仍需sql语句。比如select avg(num) amount from ****。
3,打印运行后的结果,可更深入yii这么做是如何实现的
Php代码
//可见
$c = new CDbCriteria();
$c->join = “JOIN idc_user on t.id=idc_user.user_id”;
$c->condition = “idc_user.idc_id=$idc_id”;
//运行后
object(CDbCriteria)#98 (12) { [“select”]=> string(1) “*” [“distinct”]=> bool(false) [“condition”]=> string(17) “idc_user.idc_id=6” [“params”]=> array(0) { } [“limit”]=> int(-1) [“offset”]=> int(-1) [“order”]=> string(0) “” [“group”]=> string(0) “” [“join”]=> string(38) “JOIN idc_user on t.id=idc_user.user_id” [“having”]=> string(0) “” [“with”]=> NULL [“alias”]=> NULL }
//User::model()->with(‘Idcs’)->findAll($c)
二、mergeWith的情况
Php代码
//在ActiveRecord中,增加条件限制
$this->getDbCriteria()->mergeWith(array(
‘condition’=>”idc_id IN ($ids)”,
));