解析yii数据库的增删查改

  1. 存取数据库方法

  存储第一种

  存表时候用到

  例子:

  

复制代码 代码如下:

  $post=new Post;

  $post->title='samplepost';

  $post->content='content for thesample post';

  $post->createTime=time();/$post->createTime=newCDbexpression_r('NOW()');

  $post->save();

  $user_field_data= new user_field_data;

  $user_field_data->flag=0;

  $user_field_data->user_id=$profile->id;

  $user_field_data->field_id=$_POST['emailhiden'];

  $user_field_data->value1=$_POST['email'];

  $user_field_data->save();

  注当一个表存储4次的时候,需要创建4个handle new4次

  存储第二种

  存储后我们需要找到这条记录的流水id 这样做 $profile = new profile;$profile->id;

  存储第三种

  用于更加安全的方法,来绑定变量类型 这样可以在同一个表中存储两个记录

  

复制代码 代码如下:

  $sql="insert intouser_field_data(user_id,field_id,flag,value1)values(:user_id,:field_id,:flag,:value1);";

  $command=user_field_data::model()->dbConnection->createCommand($sql);

  $command->bindParam(":user_id",$profile->id,PDO::PARAM_INT);

  $command->bindParam(":field_id",$_POST['firstnamehiden'],PDO::PARAM_INT);

  $command->bindParam(":flag",$tmpflag,PDO::PARAM_INT);

  $command->bindParam(":value1",$_POST['firstname'],PDO::PARAM_STR);

  $command->execute();

  $command->bindParam(":user_id",$profile->id,PDO::PARAM_INT);

  $command->bindParam(":field_id",$_POST['emailhiden'],PDO::PARAM_INT);

  $command->bindParam(":flag",$tmpflag,PDO::PARAM_INT);

  $command->bindParam(":value1",$_POST['email'],PDO::PARAM_STR);

  $rowchange =$command->execute();

  if( $rowchange != 0){ 修改成功 }//用来判断

  注:update delete都可以用这个方法

  $sql="delete from profile whereid=:id";

  $command=profile::model()->dbConnection->createCommand($sql);

  $command->bindParam(":id",$userid,PDO::PARAM_INT);

  $this->rowflag=$command->execute();

  $sql="update profile setpass=:pass,role=:role where id=:id";

  $command=profile::model()->dbConnection->createCommand($sql);

  $command->bindParam(":pass",$password,PDO::PARAM_STR);

  $command->bindParam(":role",$role,PDO::PARAM_INT);

  $command->bindParam(":id",$userid,PDO::PARAM_INT);

  $this->rowflag=$command->execute();

  // 同理变更updateAll()模式

  $sql="update user_field_data set flag =:flag where user_id= :user_id and field_id= :field_id ";

  原始sql语句

  $criteria = newCDbCriteria;

  $criteria->condition ='user_id = :user_id and field_id= :field_id';

  $criteria->params =array(':user_id' => $userid,':field_id'=> $fieldid);

  $arrupdate = array('flag'=> $flag);

  if(user_field_data::model()->updateAll($arrupdate,$criteria)!= 0)

  {

  更新成功后。。。

  }

  第四种更新和存储应用同一个handle 流程:

  先查询记录是否存在,若存在就更新,不存在就新创建

  注:1.第一次查询的变量,要跟save()前的变量一致。2.存储时候需要再次 new一下库对象

  

复制代码 代码如下:

  $user_field_data =user_field_data::model()->findByAttributes(

  $attributes = array('user_id'=>Yii::app()->user->user_id, 'field_id'=> $key));

  if($user_field_data !== null)

  {

  $user_field_data->value1= $value;

  $user_field_data->save();

  }

  else

  {

  $user_field_data= new user_field_data;

  $user_field_data->user_id= Yii::app()->user->user_id;

  $user_field_data->field_id= $key;

  $user_field_data->value1= $value;

  $user_field_data->save();

  }

  查询

  注:当项目没查找到整个对象会为空需要这样判定

  

复制代码 代码如下:

  if($rows !== null) 当对象不为空

  {

  returntrue;

  }else{

  returnfalse;

  }

  SELECT

  读表时候用到

  例子:

  第一种find()

  

复制代码 代码如下:

  // find thefirst row satisfying the specified condition

  $post=Post::model()->find($condition,$params);

  // find the row with postID=10

  $post=Post::model()->find('postID=:postID',array(':postID'=>10));

  同样的语句,用另种方式表示

  $criteria=new CDbCriteria;

  $criteria->select='title';// only select the 'title' column

  $criteria->condition='postID=:postID';

  $criteria->params=array(':postID'=>10);

  $post=Post::model()->find($criteria);// $params is not needed

  第二种find()

  

复制代码 代码如下:

  $post=Post::model()->find(array(

  'select'=>'title',

  'condition'=>'postID=:postID',

  'params'=>array(':postID'=>10),

  ));

  // find the row with the specified primarykey

  $post=Post::model()->findByPk($postID,$condition,$params);

  // find the row with the specified attributevalues

  $post=Post::model()->findByAttributes($attributes,$condition,$params);

  示例:

  第一种findByAttributes()

  $checkuser= user_field_data::model()->findByAttributes(

  array('user_id' =>Yii::app()->user->user_id, 'field_id'=> $fieldid));

  第二种findByAttributes()

  $checkuser =user_field_data::model()->findByAttributes(

  $attributes = array('user_id'=>Yii::app()->user->user_id, 'field_id'=> $fieldid));

  第三种当没有conditions时候,不用params

  $user_field_data=user_field_data::model()->findAllByAttributes(

  $attributes = array('user_id'=> ':user_id'),

  $condition = "field_id in(:fields)",

  $params = array(':user_id'=>Yii::app()->user->user_id, ':fields'=> "$rule->dep_fields"));

  // find the first row using the specified SQLstatement

  $post=Post::model()->findBySql($sql,$params);

  例子

  user_field_data::model()->findBySql("selectid from user_field_data where user_id = :user_id and field_id =:field_id ", array(':user_id' =>$userid,':field_id'=>$fieldid));

  此时回传的是一个对象

  第四种 添加其他条件

  http://www.yiiframework.com/doc/api/CDbCriteria#limit-detail

  $criteria = newCDbCriteria;

  $criteria->select='newtime';//选择只显示哪几个字段要与库中名字相同,但是不能COUNT(newtime) as name这样写

  $criteria->join = 'LEFT JOINPost ON Post.id=Date.id';//1.先要在relation函数中增加与Post表的关系语句2.Date::model()->with('post')->findAll($criteria)

  $criteria->group ='newtime';

  $criteria->limit = 2; //都是从0开始,选取几个

  $criteria->offset = 2;// 从哪个偏移量开始

  print_r(Date::model()->findAll($criteria));

  得到行数目或者其他数目 count

  // get the number of rows satisfying thespecified condition

  $n=Post::model()->count($condition,$params);

  // get the number of rows using the specifiedSQL statement

  $n=Post::model()->countBySql($sql,$params);

  // check if there is at least a row satisfyingthe specified condition

  $exists=Post::model()->exists($condition,$params);

  UPDATE

  例子:

  

复制代码 代码如下:

  $post=Post::model()->findByPk(10);

  $post->title='new posttitle';

  $post->save(); // save thechange to database

  // update the rows matching the specifiedcondition

  Post::model()->updateAll($attributes,$condition,$params);

  例子:或者参考上面例子

  

复制代码 代码如下:

  $c=new CDbCriteria;

  $c->condition='something=1';

  $c->limit=10;

  $a=array('name'=>'NewName');

  Post::model()->updateAll($a,$c);

  // update the rows matching the specifiedcondition and primary key(s)

  Post::model()->updateByPk($pk,$attributes,$condition,$params);

  例子

  

复制代码 代码如下:

  $profile =profile::model()->updateByPk(

  Yii::app()->user->user_id,

  $attributes = array('pass' =>md5($_POST['password']), 'role' => 1));

  // update counter columns in the rowssatisfying the specified conditions

  Post::model()->updateCounters($counters,$condition,$params);

  DELETE

  例子:

  

复制代码 代码如下:

  $post=Post::model()->findByPk(10);// assuming there is a post whose ID is 10

  $post->delete(); // delete therow from the database table

  // delete the rows matching the specifiedcondition

  Post::model()->deleteAll($condition,$params);

  // delete the rows matching the specifiedcondition and primary key(s)

  Post::model()->deleteByPk($pk,$condition,$params);

  COMPARE

  

  目前可以取出的

  1.//$allquestion=field::model()->findAllBySql("selectlabel from field where step_id = :time1 ", array(':time1'=>1));

  2. //$criteria=new CDbCriteria;

  //$criteria->select='label,options';

  //$criteria->condition='step_id=:postID';

  //$criteria->params=array(':postID'=>1);

  //$allquestion=field::model()->findAll($criteria);

  //$allquestion=field::model()->find("",array("label"));

  可以与在models文件夹中的 库连接文件relations()函数合用,这样可以联合查询

  $criteria=newCDbCriteria;

  $criteria->condition='field.step_id=1';

  $this->_post=field::model()->with('step')->findAll($criteria);

  这样出来的数组里面包含step表中的值,且这个值的条件为step.id=field.step_id

  public functionrelations()

  {

  return array(

  'step'=>array(self::BELONGS_TO,'step', 'step_id'),

  );

  }