Hi im newbie , and a have one question!
How to generate code automatically like
SPPB1508/001
SPPB
it is name of code,
1508
it is year and month,
001
it is a number that will increase when the code contained in the database.
table :
SPPB
id
no_sppb
nama_sppb
no_sppb will be filled by that code.
I hope you will help me.
sorry for my bad english , I translate it in google translate 
Welcome to the Yii forum.
The first place to start is to learn what is Gii, and how to make models and CRUD operations uisng Gii tool.
Here is a good tutorial: http://code-epicenter.com/what-is-gii-and-how-to-use-it/
Using Gii tool you can automatically make INSERT, UPDATE, DELETE, SEARCH functionalities, which will save you a lot of time.
I would do it in CActiveRecord::beforeSave() like the following:
protected function beforeSave()
{
if (parent::beforeSave()) {
if ($this->isNewRecord) {
$name = 'SPPB';
$ym = substr(date('Ym'), 2, 4);
$code = sprintf('%03d', SerialNumber::generateSerialNumber($name, $ym));
$this->no_sppb = $name . $ym . '/' . $code;
}
return true;
} else {
return false;
}
}
SerialNumber model is responsible for generating a serial number …
public static function generateSerialNumber($name, $ym)
{
$model = SerialNumber::model()->find(
'name = :name AND ym = :ym',
array(':name' => $name, ':ym' => $ym));
if (!$model) {
$model = new SerialNumber();
$model->name = $name;
$model->ym = $ym;
$model->number = 0;
}
$number = $model->number + 1;
$model->number = $number;
$model->save();
return $number;
}
Well, please note that the generateSerialNumber() method above is not perfect. It may return a wrong serial number when your app get multiple requests at the same time.
Please google for ‘LAST_INSERT_ID’ for the tips to correct the method, though it is MySQL specific.
Thanks for the answer 
copy paste this code in your model
public function generateCode() {
$_d = date("ym");
$_i = "SPPB.";
$_left = $_d;
$_first = "001";
$_len = strlen($_left);
$no = $_i . $_left .'/'. $_first;
$last_po = $this->find(
array(
"select" => "id",
"condition" => "left(id, " . $_len . ") = :_left",
"params" => array(":_left" => $_left),
"order" => "id DESC"
));
if ($last_po != null) {
$_no = substr($last_po->id, $_len);
$_no++;
$_no = substr("000", strlen($_no)) . $_no;
$no = $_i . $_left .'/'. $_no;
}
return $no;
}
and call this function like :
protected function beforeSave() {
if ($this->isNewRecord) {
$this->id = $this->generateCode();
.... // any code that you want to
} else {
.... // any code that you want to
parent::beforeSave();
}
return true;
}
this code work for me.
This code works, but stopped at number 10 and can not increase 