CDbcriteria error without using alias

Yii 1.1 General Discussion
1

This is the working code:


        	$criteria = new CDbCriteria;

        	$criteria->condition = 'user_id=:currentUserID';

        	$criteria->params = array(':currentUserID'=>$userID);

        	$criteria->alias='r';

        	$criteria->select = 'item.title, r.item_quantity';

        	$criteria->join = 'JOIN item ON item.id=r.item_id';

        	$dataProvider = new CActiveDataProvider('RecuringOrder',array('criteria'=>$criteria));

		$this->render('index', array('dataProvider'=>$dataProvider));

This code doesn’t work:




        	$criteria = new CDbCriteria;

        	$criteria->condition = 'user_id=:currentUserID';

        	$criteria->params = array(':currentUserID'=>$userID);

        	//$criteria->alias='r';

        	$criteria->select = 'item.title, recuring_order.item_quantity'; // replace alias r with recuring_order, the real table name in mySQL

        	$criteria->join = 'JOIN item ON item.id=recuring_order.item_id'; // replace alias r with recuring_order, the real table name in mySQL

        	$dataProvider = new CActiveDataProvider('RecuringOrder',array('criteria'=>$criteria));

		$this->render('index', array('dataProvider'=>$dataProvider));

CDbcriteria is the most confusing part for me. Why I have to use alias in the above situation?

Thank you very much!

2

The implicit primary table alias ‘t’ should work.

See this section of the guide.

/Tommy

3

yes, the implicit t works without alias definition. I just read the guide that you suggested.

Do you think I can make the following conclusion?

If there is same column name in two tables in a query, the primary table has to be an alias, either default "t’, or other alias, e.g. r, that you assign.

Thank you!

4

That’s my understanding.

For columns of related tables you can use the relationship name or an alias of your choice.

/Tommy