dropdownlist not working in yii - drop-down-menu

Question

the thing is i have 3 models wherein model1 model2's xyz(pid) is invoked which fetches the all id's contain that pid ,know model3 have (id,name) for the model2 fetched ids(fk of model3 id) ,i have looped them ,$data should store the name,id and a list of all id,name must appear in the dropdown of model1 view create
but i get the error stating
CDbCommand failed to execute the SQL statement: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'Array' in 'where clause'. The SQL statement executed was:
SELECT id,name
FROM table1
WHERE id = Array
model1
public function myabcDropDown()
{
$pid=Yii::app()->SESSION['pid'];
$sid=model2::model()->xyz($pid);
foreach($sid as $val) //line 0
{
$data=model3::model()->pqr($val);
$data.=$data;
}
//line 1
$datalist=CHtml::listData($data,'id','name');
return $datalist;
}
function in model3
public function pqr($val)
{
$sql="SELECT id,name
FROM table1
WHERE id = ".$val;
$connection=Yii::app()->db;
$command=$connection->createCommand($sql);
$tts=$command->queryRow();
$result=array();
foreach($tts as $key=>$val1)
{
$result[]=$val1;
}
return $result;
}
function in model2
public function xyz($pid);
{
$sql="SELECT id
FROM table3
WHERE id = ".$pid;
$connection=Yii::app()->db;
$command=$connection->createCommand($sql);
$tts=$command->queryAll();
$result=array();
foreach($tts as $key=>$val)
{
$result[]=$val;
}
return $result;
}
Please help I am losing my mind on it

Answer 1

$result of xyz() is an array of rows(which in turn are arrays of fields) not of fields since queryAll was used. Use queryRow instead.

Answer 2

You need to learn about queryScalar() as they can help you a ;lot. now looking into your code you can do this
public function xyz($pid);
{
$sql="SELECT id
FROM table3
WHERE id = ".$pid;
$connection=Yii::app()->db;
$command=$connection->createCommand($sql);
$result=$command->queryColumn();
return $result;
}
Then
public function myabcDropDown()
{
$data=array();
$pid=Yii::app()->SESSION['pid'];
$sid=model2::model()->xyz($pid);
if(!empty($sid))
{
foreach($sid as $value)
{
$data[]=model3::model()->pqr($value);
}
$datalist=CHtml::listData($data,'id','name');
return $datalist;
}
else
{
throw new CHttpException('I got no result');
}
}
and then finally
public function pqr($val)
{
$criteria=new CDbCriteria;
$criteria->select='id,name';
$criteria->condition='id=:id';
$criteria->params=array(':id'=>$val);
$result=Table1::model->find($criteria);
return $result;
}
Information:-
queryScalar() = You should use it if you are sure that your query is going to return single result only. It will make you free from the headache of arrays.
queryColumn() = You should use it if your are going to select a single column values in your query. It will return you one dimensional array and hence making you free from the headache of multidimensional arrays.

Answer 3

This wrks
public function myabcDropDown()
{
$pid=Yii::app()->SESSION['pid'];
$sid=model2::model()->xyz($pid);
$datalist=CHtml::listData($sid,'id','name');
return $datalist;
}
public function xyz($pid);
{
$sql="select id ,name from table1 where id IN (SELECT id
FROM table2
WHERE pid = ".$pid.")";
$connection=Yii::app()->db;
$command=$connection->createCommand($sql);
$tts=$command->queryAll();
$result=array();
foreach($tts as $key=>$val)
{
$result[]=$val;
}
return $result;
}
and no need od pqr() any more