MANY_MANY relation does not work for me - many-to-many

Question

I am now discovering the Yii framework and doing it by trying to develop a simple application which allows to create Leagues and assign Players to it. The relationship between these is many to many (a player can subscribe to many leagues, and one league contains many players). So I have three db tables - tbl_league, tbl_player and tbl_league_player and I created foreign keys like this:
ALTER TABLE tbl_league_player ADD FOREIGN KEY league_id_idxfk (league_id) REFERENCES tbl_league (id);
ALTER TABLE tbl_league_player ADD FOREIGN KEY player_id_idxfk (player_id) REFERENCES tbl_player (id);
Now I am trying to display League with the list of all players subscribed to it, so my actionView in LeagueController says:
public function actionView($id)
{
$issueDataProvider = new CActiveDataProvider('Player', array(
'criteria' => array(
'condition' => 'league_id=:leagueId',
'params' => array(
':leagueId' => $this->loadModel($id)->id
),
),
'pagination' => array(
'pageSize' => 1,
),
));
$this->render('view',array(
'model'=>$this->loadModel($id),
'issueDataProvider' => $issueDataProvider,
));
}
What I am trying to do here is to get all players from the Player table subscribed to a particular league ID. For this I have the Player model with relation defined like this:
public function relations()
{
// NOTE: you may need to adjust the relation name and the related
// class name for the relations automatically generated below.
return array(
'League' => array(self::MANY_MANY, 'League', 'tbl_league_player(player_id, league_id)'),
);
}
The problem is that I go to, for example, league/view&id=2, I am getting this error: "SELECT COUNT(*) FROM tbl_player t WHERE league_id=:leagueId" so it looks like the relation does not work. What am I missing?
Thanks a lot!

Answer 1

So, first, the reason for the error is that you are adding a WHERE league_id = condition to your Player CActiveDataProvider, and your Player table does not have a league_id column.
What you should do to get a list of the players in your View is:
1) NOT make a CActiveDataProvider - just pass in the $model to your view
public function actionView($id)
{
$this->render('view',array(
'model'=>$this->loadModel($id),
));
}
2) Then, in your view, just lazy-load your MANY_MANY relation and loop through it like so:
<?php foreach($model->League as $player): ?>
<?php echo $player->name ?>
<?php endforeach; ?>
I would rename your "League" relation "players" or something.
If you really need to use a CActiveDataProvider... I can't remember how to (or if you can) pass in a a relation, but you can do it my manually adding join criteria to your CActiveDataProvider.
I hope this helps! Cheers

Answer 2

try this.
Inside LeagueController
public function actionView($id)
{
$criteria=new CDbCriteria;
$criteria->with='League';
$criteria->together=true;
$criteria->condition='league_id=:leagueId';
$criteria->params=array(':leagueId'=>$this->loadModel($id)->id);
$issueDataProvider = new CActiveDataProvider('Player',array(
'criteria'=>$criteria,
),
'pagination' => array(
'pageSize' => 1,
),
));