Question

For these three tables, Table XXX has two column composite PK:

Table XXX:
 - XXX_id_1
 - XXX_id_2
 - name

Table YYY:
 - YYY_id
 - name

Table XXX_has_YYY:
 - X_id
 - Y_id
 - A_id

How can I define this relation in Yii’s ORM?

public function relations() {
  return array(
      'YYY' => array(self::MANY_MANY, 'YYY',
          'XXX_has_YYY(XXX_id_1, XXX_id_2, YYY_id)'),
  );
}

Answer 1

Please read the documentation.

Note, for composite foreign keys, they can be either listed together, separated by commas or specified as an array in format of array(‘key1′,’key2’). In case you need to specify custom PK->FK association you can define it as array(‘fk’=>’pk’). For composite keys it will be array(‘fk_c1’=>’pk_с1′,’fk_c2’=>’pk_c2’).

Also, the second argument refers to the name of the active record class that the related object is of.
Your relation therefore should look something like this:

'XXX_has_YYY_relation_name' => array(self::MANY_MANY, XXX_has_YYY, array(XXX_id_1, XXX_id_2, YYY_id) ),